diff --git a/.travis.yml b/.travis.yml
index a79fd98b97..86ae88730c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -207,6 +207,7 @@ install:
 
       if [[ ! $deps ]]; then
           php .github/build-packages.php HEAD^ src/Symfony/Bridge/PhpUnit src/Symfony/Contracts
+          composer remove --dev --no-update paragonie/sodium_compat
       else
           export SYMFONY_DEPRECATIONS_HELPER=weak &&
           cp composer.json composer.json.orig &&
diff --git a/composer.json b/composer.json
index ef3906cb32..d6c555b201 100644
--- a/composer.json
+++ b/composer.json
@@ -113,6 +113,7 @@
         "monolog/monolog": "^1.25.1",
         "nyholm/psr7": "^1.0",
         "ocramius/proxy-manager": "^2.1",
+        "paragonie/sodium_compat": "^1.8",
         "php-http/httplug": "^1.0|^2.0",
         "predis/predis": "~1.1",
         "psr/http-client": "^1.0",
diff --git a/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md b/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
index 093f4bb1da..eb9f8fc486 100644
--- a/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
+++ b/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
@@ -17,6 +17,7 @@ CHANGELOG
  * Added new `error_controller` configuration to handle system exceptions
  * Added sort option for `translation:update` command.
  * [BC Break] The `framework.messenger.routing.senders` config key is not deep merged anymore.
+ * Added `secrets:*` commands and `%env(secret:...)%` processor to deal with secrets seamlessly.
 
 4.3.0
 -----
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/SecretsDecryptToLocalCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsDecryptToLocalCommand.php
new file mode 100644
index 0000000000..c9370768f0
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsDecryptToLocalCommand.php
@@ -0,0 +1,90 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Command;
+
+use Symfony\Bundle\FrameworkBundle\Secrets\AbstractVault;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\ConsoleOutputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+final class SecretsDecryptToLocalCommand extends Command
+{
+    protected static $defaultName = 'secrets:decrypt-to-local';
+
+    private $vault;
+    private $localVault;
+
+    public function __construct(AbstractVault $vault, AbstractVault $localVault = null)
+    {
+        $this->vault = $vault;
+        $this->localVault = $localVault;
+
+        parent::__construct();
+    }
+
+    protected function configure()
+    {
+        $this
+            ->setDescription('Decrypts all secrets and stores them in the local vault.')
+            ->addOption('force', 'f', InputOption::VALUE_NONE, 'Forces overriding of secrets that already exist in the local vault')
+            ->setHelp(<<<'EOF'
+The <info>%command.name%</info> command list decrypts all secrets and stores them in the local vault..
+
+    <info>%command.full_name%</info>
+
+When the option <info>--force</info> is provided, secrets that already exist in the local vault are overriden.
+
+    <info>%command.full_name% --force</info>
+EOF
+            )
+        ;
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output);
+
+        if (null === $this->localVault) {
+            $io->error('The local vault is disabled.');
+
+            return 1;
+        }
+
+        $secrets = $this->vault->list(true);
+
+        if (!$input->getOption('force')) {
+            foreach ($this->localVault->list() as $k => $v) {
+                unset($secrets[$k]);
+            }
+        }
+
+        foreach ($secrets as $k => $v) {
+            if (null === $v) {
+                $io->error($this->vault->getLastMessage());
+
+                return 1;
+            }
+
+            $this->localVault->seal($k, $v);
+        }
+
+        return 0;
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/SecretsEncryptFromLocalCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsEncryptFromLocalCommand.php
new file mode 100644
index 0000000000..3161a21982
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsEncryptFromLocalCommand.php
@@ -0,0 +1,90 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Command;
+
+use Symfony\Bundle\FrameworkBundle\Secrets\AbstractVault;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\ConsoleOutputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+final class SecretsEncryptFromLocalCommand extends Command
+{
+    protected static $defaultName = 'secrets:encrypt-from-local';
+
+    private $vault;
+    private $localVault;
+
+    public function __construct(AbstractVault $vault, AbstractVault $localVault = null)
+    {
+        $this->vault = $vault;
+        $this->localVault = $localVault;
+
+        parent::__construct();
+    }
+
+    protected function configure()
+    {
+        $this
+            ->setDescription('Encrypts all local secrets to the vault.')
+            ->addOption('force', 'f', InputOption::VALUE_NONE, 'Forces overriding of secrets that already exist in the vault')
+            ->setHelp(<<<'EOF'
+The <info>%command.name%</info> command list encrypts all local secrets and stores them in the vault..
+
+    <info>%command.full_name%</info>
+
+When the option <info>--force</info> is provided, secrets that already exist in the vault are overriden.
+
+    <info>%command.full_name% --force</info>
+EOF
+            )
+        ;
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output);
+
+        if (null === $this->localVault) {
+            $io->error('The local vault is disabled.');
+
+            return 1;
+        }
+
+        $secrets = $this->localVault->list(true);
+
+        if (!$input->getOption('force')) {
+            foreach ($this->vault->list() as $k => $v) {
+                unset($secrets[$k]);
+            }
+        }
+
+        foreach ($secrets as $k => $v) {
+            if (null === $v) {
+                $io->error($this->localVault->getLastMessage());
+
+                return 1;
+            }
+
+            $this->vault->seal($k, $v);
+        }
+
+        return 0;
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/SecretsGenerateKeysCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsGenerateKeysCommand.php
new file mode 100644
index 0000000000..f56fd0fe6c
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsGenerateKeysCommand.php
@@ -0,0 +1,125 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Command;
+
+use Symfony\Bundle\FrameworkBundle\Secrets\AbstractVault;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\ConsoleOutputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+/**
+ * @author Tobias Schultze <http://tobion.de>
+ * @author Jérémy Derussé <jeremy@derusse.com>
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+final class SecretsGenerateKeysCommand extends Command
+{
+    protected static $defaultName = 'secrets:generate-keys';
+
+    private $vault;
+    private $localVault;
+
+    public function __construct(AbstractVault $vault, AbstractVault $localVault = null)
+    {
+        $this->vault = $vault;
+        $this->localVault = $localVault;
+
+        parent::__construct();
+    }
+
+    protected function configure()
+    {
+        $this
+            ->setDescription('Generates new encryption keys.')
+            ->addOption('local', 'l', InputOption::VALUE_NONE, 'Updates the local vault.')
+            ->addOption('rotate', 'r', InputOption::VALUE_NONE, 'Re-encrypts existing secrets with the newly generated keys.')
+            ->setHelp(<<<'EOF'
+The <info>%command.name%</info> command generates a new encryption key.
+
+    <info>%command.full_name%</info>
+
+If encryption keys already exist, the command must be called with
+the <info>--rotate</info> option in order to override those keys and re-encrypt
+existing secrets.
+
+    <info>%command.full_name% --rotate</info>
+EOF
+            )
+        ;
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output);
+        $vault = $input->getOption('local') ? $this->localVault : $this->vault;
+
+        if (null === $vault) {
+            $io->success('The local vault is disabled.');
+
+            return 1;
+        }
+
+        if (!$input->getOption('rotate')) {
+            if ($vault->generateKeys()) {
+                $io->success($vault->getLastMessage());
+
+                if ($this->vault === $vault) {
+                    $io->caution('DO NOT COMMIT THE DECRYPTION KEY FOR THE PROD ENVIRONMENT⚠️');
+                }
+
+                return 0;
+            }
+
+            $io->warning($vault->getLastMessage());
+
+            return 1;
+        }
+
+        $secrets = [];
+        foreach ($vault->list(true) as $name => $value) {
+            if (null === $value) {
+                $io->error($vault->getLastMessage());
+
+                return 1;
+            }
+
+            $secrets[$name] = $value;
+        }
+
+        if (!$vault->generateKeys(true)) {
+            $io->warning($vault->getLastMessage());
+
+            return 1;
+        }
+
+        $io->success($vault->getLastMessage());
+
+        if ($secrets) {
+            foreach ($secrets as $name => $value) {
+                $vault->seal($name, $value);
+            }
+
+            $io->comment('Existing secrets have been rotated to the new keys.');
+        }
+
+        if ($this->vault === $vault) {
+            $io->caution('DO NOT COMMIT THE DECRYPTION KEY FOR THE PROD ENVIRONMENT⚠️');
+        }
+
+        return 0;
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/SecretsListCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsListCommand.php
new file mode 100644
index 0000000000..4ae190435d
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsListCommand.php
@@ -0,0 +1,108 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Command;
+
+use Symfony\Bundle\FrameworkBundle\Secrets\AbstractVault;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Helper\Dumper;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\ConsoleOutputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+/**
+ * @author Tobias Schultze <http://tobion.de>
+ * @author Jérémy Derussé <jeremy@derusse.com>
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+final class SecretsListCommand extends Command
+{
+    protected static $defaultName = 'secrets:list';
+
+    private $vault;
+    private $localVault;
+
+    public function __construct(AbstractVault $vault, AbstractVault $localVault = null)
+    {
+        $this->vault = $vault;
+        $this->localVault = $localVault;
+
+        parent::__construct();
+    }
+
+    protected function configure()
+    {
+        $this
+            ->setDescription('Lists all secrets.')
+            ->addOption('reveal', 'r', InputOption::VALUE_NONE, 'Display decrypted values alongside names')
+            ->setHelp(<<<'EOF'
+The <info>%command.name%</info> command list all stored secrets.
+
+    <info>%command.full_name%</info>
+
+When the option <info>--reveal</info> is provided, the decrypted secrets are also displayed.
+
+    <info>%command.full_name% --reveal</info>
+EOF
+            )
+        ;
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output);
+
+        $io->comment('Use <info>"%env(secret:<name>)%"</info> to reference a secret in a config file.');
+
+        if (!$reveal = $input->getOption('reveal')) {
+            $io->comment(sprintf('To reveal the secrets run <info>php %s %s --reveal</info>', $_SERVER['PHP_SELF'], $this->getName()));
+        }
+
+        $secrets = $this->vault->list($reveal);
+        $localSecrets = null !== $this->localVault ? $this->localVault->list($reveal) : null;
+
+        $rows = [];
+
+        $dump = new Dumper($output);
+        $dump = static function (?string $v) use ($dump) {
+            return null === $v ? '******' : $dump($v);
+        };
+
+        foreach ($secrets as $name => $value) {
+            $rows[$name] = [$name, $dump($value)];
+        }
+
+        if (null !== $message = $this->vault->getLastMessage()) {
+            $io->comment($message);
+        }
+
+        foreach ($localSecrets ?? [] as $name => $value) {
+            $rows[$name] = [$name, $rows[$name][1] ?? '', $dump($value)];
+        }
+
+        uksort($rows, 'strnatcmp');
+
+        if (null !== $this->localVault && null !== $message = $this->localVault->getLastMessage()) {
+            $io->comment($message);
+        }
+
+        (new SymfonyStyle($input, $output))
+            ->table(['Secret', 'Value'] + (null !== $localSecrets ? [2 => 'Local Value'] : []), $rows);
+
+        $io->comment("Local values override secret values.\nUse <info>secrets:set --local</info> to defined them.");
+
+        return 0;
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/SecretsRemoveCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsRemoveCommand.php
new file mode 100644
index 0000000000..b0ce9a89fe
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsRemoveCommand.php
@@ -0,0 +1,82 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Command;
+
+use Symfony\Bundle\FrameworkBundle\Secrets\AbstractVault;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\ConsoleOutputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+/**
+ * @author Jérémy Derussé <jeremy@derusse.com>
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+final class SecretsRemoveCommand extends Command
+{
+    protected static $defaultName = 'secrets:remove';
+
+    private $vault;
+    private $localVault;
+
+    public function __construct(AbstractVault $vault, AbstractVault $localVault = null)
+    {
+        $this->vault = $vault;
+        $this->localVault = $localVault;
+
+        parent::__construct();
+    }
+
+    protected function configure()
+    {
+        $this
+            ->setDescription('Removes a secret from the vault.')
+            ->addArgument('name', InputArgument::REQUIRED, 'The name of the secret')
+            ->addOption('local', 'l', InputOption::VALUE_NONE, 'Updates the local vault.')
+            ->setHelp(<<<'EOF'
+The <info>%command.name%</info> command removes a secret from the vault.
+
+    <info>%command.full_name% <name></info>
+EOF
+            )
+        ;
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output);
+        $vault = $input->getOption('local') ? $this->localVault : $this->vault;
+
+        if (null === $vault) {
+            $io->success('The local vault is disabled.');
+
+            return 1;
+        }
+
+        if ($vault->remove($name = $input->getArgument('name'))) {
+            $io->success($vault->getLastMessage() ?? 'Secret was removed from the vault.');
+        } else {
+            $io->comment($vault->getLastMessage() ?? 'Secret was not found in the vault.');
+        }
+
+        if ($this->vault === $vault && null !== $this->localVault->reveal($name)) {
+            $io->comment('Note that this secret is overridden in the local vault.');
+        }
+
+        return 0;
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/SecretsSetCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsSetCommand.php
new file mode 100644
index 0000000000..850cf08ee3
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/SecretsSetCommand.php
@@ -0,0 +1,134 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Command;
+
+use Symfony\Bundle\FrameworkBundle\Secrets\AbstractVault;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\ConsoleOutputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+/**
+ * @author Tobias Schultze <http://tobion.de>
+ * @author Jérémy Derussé <jeremy@derusse.com>
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+final class SecretsSetCommand extends Command
+{
+    protected static $defaultName = 'secrets:set';
+
+    private $vault;
+    private $localVault;
+
+    public function __construct(AbstractVault $vault, AbstractVault $localVault = null)
+    {
+        $this->vault = $vault;
+        $this->localVault = $localVault;
+
+        parent::__construct();
+    }
+
+    protected function configure()
+    {
+        $this
+            ->setDescription('Sets a secret in the vault.')
+            ->addArgument('name', InputArgument::REQUIRED, 'The name of the secret')
+            ->addArgument('file', InputArgument::OPTIONAL, 'A file where to read the secret from or "-" for reading from STDIN')
+            ->addOption('local', 'l', InputOption::VALUE_NONE, 'Updates the local vault.')
+            ->addOption('random', 'r', InputOption::VALUE_OPTIONAL, 'Generates a random value.', false)
+            ->setHelp(<<<'EOF'
+The <info>%command.name%</info> command stores a secret in the vault.
+
+    <info>%command.full_name% <name></info>
+
+To reference secrets in services.yaml or any other config
+files, use <info>"%env(secret:<name>)%"</info>.
+
+By default, the secret value should be entered interactively.
+Alternatively, provide a file where to read the secret from:
+
+    <info>php %command.full_name% <name> filename</info>
+
+Use "-" as a file name to read from STDIN:
+
+    <info>cat filename | php %command.full_name% <name> -</info>
+
+Use <info>--local</info> to override secrets for local needs.
+EOF
+            )
+        ;
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $errOutput = $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output;
+        $io = new SymfonyStyle($input, $errOutput);
+        $name = $input->getArgument('name');
+        $vault = $input->getOption('local') ? $this->localVault : $this->vault;
+
+        if (null === $vault) {
+            $io->error('The local vault is disabled.');
+
+            return 1;
+        }
+
+        if (0 < $random = $input->getOption('random') ?? 16) {
+            $value = strtr(substr(base64_encode(random_bytes($random)), 0, $random), '+/', '-_');
+        } elseif (!$file = $input->getArgument('file')) {
+            $value = $io->askHidden('Please type the secret value');
+        } elseif ('-' === $file) {
+            $value = file_get_contents('php://stdin');
+        } elseif (is_file($file) && is_readable($file)) {
+            $value = file_get_contents($file);
+        } elseif (!is_file($file)) {
+            throw new \InvalidArgumentException(sprintf('File not found: "%s".', $file));
+        } elseif (!is_readable($file)) {
+            throw new \InvalidArgumentException(sprintf('File is not readable: "%s".', $file));
+        }
+
+        if (null === $value) {
+            $io->warning('No value provided, aborting.');
+
+            return 1;
+        }
+
+        if ($vault->generateKeys()) {
+            $io->success($vault->getLastMessage());
+
+            if ($this->vault === $vault) {
+                $io->caution('DO NOT COMMIT THE DECRYPTION KEY FOR THE PROD ENVIRONMENT⚠️');
+            }
+        }
+
+        $vault->seal($name, $value);
+
+        $io->success($vault->getLastMessage() ?? 'Secret was successfully stored in the vault.');
+
+        if (0 < $random) {
+            $errOutput->write(' // The generated random value is: <comment>');
+            $output->write($value);
+            $errOutput->writeln('</comment>');
+            $io->newLine();
+        }
+
+        if ($this->vault === $vault && null !== $this->localVault->reveal($name)) {
+            $io->comment('Note that this secret is overridden in the local vault.');
+        }
+
+        return 0;
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php
index c34377fa0d..3520d9962d 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php
@@ -115,10 +115,27 @@ class Configuration implements ConfigurationInterface
         $this->addRobotsIndexSection($rootNode);
         $this->addHttpClientSection($rootNode);
         $this->addMailerSection($rootNode);
+        $this->addSecretsSection($rootNode);
 
         return $treeBuilder;
     }
 
+    private function addSecretsSection(ArrayNodeDefinition $rootNode)
+    {
+        $rootNode
+            ->children()
+                ->arrayNode('secrets')
+                    ->canBeDisabled()
+                    ->children()
+                        ->scalarNode('vault_directory')->defaultValue('%kernel.project_dir%/config/secrets/%kernel.environment%')->cannotBeEmpty()->end()
+                        ->scalarNode('local_dotenv_file')->defaultValue('%kernel.project_dir%/.env.local')->end()
+                        ->scalarNode('decryption_env_var')->defaultValue('base64:default::SYMFONY_DECRYPTION_SECRET')->end()
+                    ->end()
+                ->end()
+            ->end()
+        ;
+    }
+
     private function addCsrfSection(ArrayNodeDefinition $rootNode)
     {
         $rootNode
diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
index 1d83148ff7..2c8d080859 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
@@ -334,6 +334,7 @@ class FrameworkExtension extends Extension
         $this->registerRouterConfiguration($config['router'], $container, $loader);
         $this->registerAnnotationsConfiguration($config['annotations'], $container, $loader);
         $this->registerPropertyAccessConfiguration($config['property_access'], $container, $loader);
+        $this->registerSecretsConfiguration($config['secrets'], $container, $loader);
 
         if ($this->isConfigEnabled($container, $config['serializer'])) {
             if (!class_exists('Symfony\Component\Serializer\Serializer')) {
@@ -1441,6 +1442,34 @@ class FrameworkExtension extends Extension
         ;
     }
 
+    private function registerSecretsConfiguration(array $config, ContainerBuilder $container, XmlFileLoader $loader)
+    {
+        if (!$this->isConfigEnabled($container, $config)) {
+            $container->removeDefinition('console.command.secrets_set');
+            $container->removeDefinition('console.command.secrets_list');
+            $container->removeDefinition('console.command.secrets_remove');
+            $container->removeDefinition('console.command.secrets_generate_key');
+            $container->removeDefinition('console.command.secrets_decrypt_to_local');
+            $container->removeDefinition('console.command.secrets_encrypt_from_local');
+
+            return;
+        }
+
+        $loader->load('secrets.xml');
+
+        $container->getDefinition('secrets.vault')->replaceArgument(0, $config['vault_directory']);
+
+        if (!$config['local_dotenv_file']) {
+            $container->removeDefinition('secrets.local_vault');
+        }
+
+        if ($config['decryption_env_var']) {
+            $container->getDefinition('secrets.decryption_key')->replaceArgument(1, $config['decryption_env_var']);
+        } else {
+            $container->removeDefinition('secrets.decryption_key');
+        }
+    }
+
     private function registerSecurityCsrfConfiguration(array $config, ContainerBuilder $container, XmlFileLoader $loader)
     {
         if (!$this->isConfigEnabled($container, $config)) {
diff --git a/src/Symfony/Bundle/FrameworkBundle/Resources/config/console.xml b/src/Symfony/Bundle/FrameworkBundle/Resources/config/console.xml
index f13aa759d3..9a586e0a58 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Resources/config/console.xml
+++ b/src/Symfony/Bundle/FrameworkBundle/Resources/config/console.xml
@@ -200,5 +200,41 @@
             <argument type="service" id="debug.file_link_formatter" on-invalid="null" />
             <tag name="console.command" command="debug:error-renderer" />
         </service>
+
+        <service id="console.command.secrets_set" class="Symfony\Bundle\FrameworkBundle\Command\SecretsSetCommand">
+            <argument type="service" id="secrets.vault" />
+            <argument type="service" id="secrets.local_vault" on-invalid="ignore" />
+            <tag name="console.command" command="secrets:set" />
+        </service>
+
+        <service id="console.command.secrets_remove" class="Symfony\Bundle\FrameworkBundle\Command\SecretsRemoveCommand">
+            <argument type="service" id="secrets.vault" />
+            <argument type="service" id="secrets.local_vault" on-invalid="ignore" />
+            <tag name="console.command" command="secrets:remove" />
+        </service>
+
+        <service id="console.command.secrets_generate_key" class="Symfony\Bundle\FrameworkBundle\Command\SecretsGenerateKeysCommand">
+            <argument type="service" id="secrets.vault" />
+            <argument type="service" id="secrets.local_vault" on-invalid="ignore" />
+            <tag name="console.command" command="secrets:generate-keys" />
+        </service>
+
+        <service id="console.command.secrets_list" class="Symfony\Bundle\FrameworkBundle\Command\SecretsListCommand">
+            <argument type="service" id="secrets.vault" />
+            <argument type="service" id="secrets.local_vault" on-invalid="ignore" />
+            <tag name="console.command" command="secrets:list" />
+        </service>
+
+        <service id="console.command.secrets_decrypt_to_local" class="Symfony\Bundle\FrameworkBundle\Command\SecretsDecryptToLocalCommand">
+            <argument type="service" id="secrets.vault" />
+            <argument type="service" id="secrets.local_vault" on-invalid="ignore" />
+            <tag name="console.command" command="secrets:decrypt-to-local" />
+        </service>
+
+        <service id="console.command.secrets_encrypt_from_local" class="Symfony\Bundle\FrameworkBundle\Command\SecretsEncryptFromLocalCommand">
+            <argument type="service" id="secrets.vault" />
+            <argument type="service" id="secrets.local_vault" on-invalid="ignore" />
+            <tag name="console.command" command="secrets:encrypt-from-local" />
+        </service>
     </services>
 </container>
diff --git a/src/Symfony/Bundle/FrameworkBundle/Resources/config/secrets.xml b/src/Symfony/Bundle/FrameworkBundle/Resources/config/secrets.xml
new file mode 100644
index 0000000000..d0ba0bcb34
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Resources/config/secrets.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" ?>
+
+<container xmlns="http://symfony.com/schema/dic/services"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://symfony.com/schema/dic/services https://symfony.com/schema/dic/services/services-1.0.xsd">
+
+    <services>
+        <service id="secrets.vault" class="Symfony\Bundle\FrameworkBundle\Secrets\SodiumVault">
+            <argument>%kernel.project_dir%/config/secrets/%kernel.environment%</argument>
+            <argument type="service" id="secrets.decryption_key" on-invalid="ignore" />
+        </service>
+
+        <!--
+            LazyString::fromCallable() is used as a wrapper to lazily read the SYMFONY_DECRYPTION_SECRET var from the env.
+            By overriding this service and using the same strategy, the decryption key can be fetched lazily from any other service if needed.
+        -->
+        <service id="secrets.decryption_key" class="Symfony\Component\DependencyInjection\LazyString">
+            <factory class="Symfony\Component\DependencyInjection\LazyString" method="fromCallable" />
+            <argument type="service">
+                <service class="Closure">
+                    <factory class="Closure" method="fromCallable" />
+                    <argument type="collection">
+                        <argument type="service" id="service_container" />
+                        <argument>getEnv</argument>
+                    </argument>
+                </service>
+            </argument>
+            <argument>base64:default::SYMFONY_DECRYPTION_SECRET</argument>
+        </service>
+
+        <service id="secrets.local_vault" class="Symfony\Bundle\FrameworkBundle\Secrets\DotenvVault">
+            <argument>%kernel.project_dir%/.env.local</argument>
+        </service>
+
+        <service id="secrets.env_var_processor" class="Symfony\Bundle\FrameworkBundle\Secrets\SecretEnvVarProcessor">
+            <argument type="service" id="secrets.vault" />
+            <argument type="service" id="secrets.local_vault" on-invalid="ignore" />
+            <tag name="container.env_var_processor" />
+        </service>
+    </services>
+</container>
diff --git a/src/Symfony/Bundle/FrameworkBundle/Secrets/AbstractVault.php b/src/Symfony/Bundle/FrameworkBundle/Secrets/AbstractVault.php
new file mode 100644
index 0000000000..eeecbbb68b
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Secrets/AbstractVault.php
@@ -0,0 +1,49 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Secrets;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+abstract class AbstractVault
+{
+    protected $lastMessage;
+
+    public function getLastMessage(): ?string
+    {
+        return $this->lastMessage;
+    }
+
+    abstract public function generateKeys(bool $override = false): bool;
+
+    abstract public function seal(string $name, string $value): void;
+
+    abstract public function reveal(string $name): ?string;
+
+    abstract public function remove(string $name): bool;
+
+    abstract public function list(bool $reveal = false): array;
+
+    protected function validateName(string $name): void
+    {
+        if (!preg_match('/^\w++$/D', $name)) {
+            throw new \LogicException(sprintf('Invalid secret name "%s": only "word" characters are allowed.', $name));
+        }
+    }
+
+    protected function getPrettyPath(string $path)
+    {
+        return str_replace(getcwd().\DIRECTORY_SEPARATOR, '', $path);
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Secrets/DotenvVault.php b/src/Symfony/Bundle/FrameworkBundle/Secrets/DotenvVault.php
new file mode 100644
index 0000000000..16df2a6045
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Secrets/DotenvVault.php
@@ -0,0 +1,110 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Secrets;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+class DotenvVault extends AbstractVault
+{
+    private $dotenvFile;
+
+    public function __construct(string $dotenvFile)
+    {
+        $this->dotenvFile = strtr($dotenvFile, '/', \DIRECTORY_SEPARATOR);
+    }
+
+    public function generateKeys(bool $override = false): bool
+    {
+        $this->lastMessage = 'The dotenv vault doesn\'t encrypt secrets thus doesn\'t need keys.';
+
+        return false;
+    }
+
+    public function seal(string $name, string $value): void
+    {
+        $this->lastMessage = null;
+        $this->validateName($name);
+        $k = $name.'_SECRET';
+        $v = str_replace("'", "'\\''", $value);
+
+        $content = file_exists($this->dotenvFile) ? file_get_contents($this->dotenvFile) : '';
+        $content = preg_replace("/^$k=((\\\\'|'[^']++')++|.*)/m", "$k='$v'", $content, -1, $count);
+
+        if (!$count) {
+            $content .= "$k='$v'\n";
+        }
+
+        file_put_contents($this->dotenvFile, $content);
+
+        $this->lastMessage = sprintf('Secret "%s" %s in "%s".', $name, $count ? 'added' : 'updated', $this->getPrettyPath($this->dotenvFile));
+    }
+
+    public function reveal(string $name): ?string
+    {
+        $this->lastMessage = null;
+        $this->validateName($name);
+        $k = $name.'_SECRET';
+        $v = \is_string($_SERVER[$k] ?? null) ? $_SERVER[$k] : ($_ENV[$k] ?? null);
+
+        if (null === $v) {
+            $this->lastMessage = sprintf('Secret "%s" not found in "%s".', $name, $this->getPrettyPath($this->dotenvFile));
+
+            return null;
+        }
+
+        return $v;
+    }
+
+    public function remove(string $name): bool
+    {
+        $this->lastMessage = null;
+        $this->validateName($name);
+        $k = $name.'_SECRET';
+
+        $content = file_exists($this->dotenvFile) ? file_get_contents($this->dotenvFile) : '';
+        $content = preg_replace("/^$k=((\\\\'|'[^']++')++|.*)\n?/m", '', $content, -1, $count);
+
+        if ($count) {
+            file_put_contents($this->dotenvFile, $content);
+            $this->lastMessage = sprintf('Secret "%s" removed from file "%s".', $name, $this->getPrettyPath($this->dotenvFile));
+
+            return true;
+        }
+
+        $this->lastMessage = sprintf('Secret "%s" not found in "%s".', $name, $this->getPrettyPath($this->dotenvFile));
+
+        return false;
+    }
+
+    public function list(bool $reveal = false): array
+    {
+        $this->lastMessage = null;
+        $secrets = [];
+
+        foreach ($_ENV as $k => $v) {
+            if (preg_match('/^(\w+)_SECRET$/D', $k, $m)) {
+                $secrets[$m[1]] = $reveal ? $v : null;
+            }
+        }
+
+        foreach ($_SERVER as $k => $v) {
+            if (\is_string($v) && preg_match('/^(\w+)_SECRET$/D', $k, $m)) {
+                $secrets[$m[1]] = $reveal ? $v : null;
+            }
+        }
+
+        return $secrets;
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Secrets/SecretEnvVarProcessor.php b/src/Symfony/Bundle/FrameworkBundle/Secrets/SecretEnvVarProcessor.php
new file mode 100644
index 0000000000..5a4771fa36
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Secrets/SecretEnvVarProcessor.php
@@ -0,0 +1,59 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Secrets;
+
+use Symfony\Component\DependencyInjection\EnvVarProcessorInterface;
+use Symfony\Component\DependencyInjection\Exception\EnvNotFoundException;
+
+/**
+ * @author Tobias Schultze <http://tobion.de>
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+class SecretEnvVarProcessor implements EnvVarProcessorInterface
+{
+    private $vault;
+    private $localVault;
+
+    public function __construct(AbstractVault $vault, AbstractVault $localVault = null)
+    {
+        $this->vault = $vault;
+        $this->localVault = $localVault;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public static function getProvidedTypes()
+    {
+        return [
+            'secret' => 'string',
+        ];
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getEnv($prefix, $name, \Closure $getEnv)
+    {
+        if (null !== $this->localVault && null !== $secret = $this->localVault->reveal($name)) {
+            return $secret;
+        }
+
+        if (null !== $secret = $this->vault->reveal($name)) {
+            return $secret;
+        }
+
+        throw new EnvNotFoundException($this->vault->getLastMessage() ?? sprintf('Secret "%s" not found or decryption key is missing.', $name));
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Secrets/SodiumVault.php b/src/Symfony/Bundle/FrameworkBundle/Secrets/SodiumVault.php
new file mode 100644
index 0000000000..8aae669d8f
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Secrets/SodiumVault.php
@@ -0,0 +1,176 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Secrets;
+
+/**
+ * @author Tobias Schultze <http://tobion.de>
+ * @author Jérémy Derussé <jeremy@derusse.com>
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+class SodiumVault extends AbstractVault
+{
+    private $encryptionKey;
+    private $decryptionKey;
+    private $pathPrefix;
+
+    /**
+     * @param string|object|null $decryptionKey A string or a stringable object that defines the private key to use to decrypt the vault
+     *                                          or null to store generated keys in the provided $secretsDir
+     */
+    public function __construct(string $secretsDir, $decryptionKey = null)
+    {
+        if (!\function_exists('sodium_crypto_box_seal')) {
+            throw new \LogicException('The "sodium" PHP extension is required to deal with secrets. Alternatively, try running "composer require paragonie/sodium_compat" if you cannot enable the extension."');
+        }
+
+        if (null !== $decryptionKey && !\is_string($decryptionKey) && !(\is_object($decryptionKey) && method_exists($decryptionKey, '__toString'))) {
+            throw new \TypeError(sprintf('Decryption key should be a string or an object that implements the __toString() method, %s given.', \gettype($decryptionKey)));
+        }
+
+        if (!is_dir($secretsDir) && !@mkdir($secretsDir, 0777, true) && !is_dir($secretsDir)) {
+            throw new \RuntimeException(sprintf('Unable to create the secrets directory (%s)', $secretsDir));
+        }
+
+        $this->pathPrefix = rtrim(strtr($secretsDir, '/', \DIRECTORY_SEPARATOR), \DIRECTORY_SEPARATOR).\DIRECTORY_SEPARATOR.basename($secretsDir).'.';
+        $this->decryptionKey = $decryptionKey;
+    }
+
+    public function generateKeys(bool $override = false): bool
+    {
+        $this->lastMessage = null;
+
+        if (null === $this->encryptionKey && '' !== $this->decryptionKey = (string) $this->decryptionKey) {
+            throw new \LogicException('Cannot generate keys when a decryption key has been provided while instantiating the vault.');
+        }
+
+        try {
+            $this->loadKeys();
+        } catch (\LogicException $e) {
+            // ignore failures to load keys
+        }
+
+        if ('' !== $this->decryptionKey && !file_exists($this->pathPrefix.'sodium.encrypt.public')) {
+            $this->export('sodium.encrypt.public', $this->encryptionKey);
+        }
+
+        if (!$override && null !== $this->encryptionKey) {
+            $this->lastMessage = sprintf('Sodium keys already exist at "%s*.{public,private}" and won\'t be overridden.', $this->getPrettyPath($this->pathPrefix));
+
+            return false;
+        }
+
+        $this->decryptionKey = sodium_crypto_box_keypair();
+        $this->encryptionKey = sodium_crypto_box_publickey($this->decryptionKey);
+
+        $this->export('sodium.encrypt.public', $this->encryptionKey);
+        $this->export('sodium.decrypt.private', $this->decryptionKey);
+
+        $this->lastMessage = sprintf('Sodium keys have been generated at "%s*.{public,private}".', $this->getPrettyPath($this->pathPrefix));
+
+        return true;
+    }
+
+    public function seal(string $name, string $value): void
+    {
+        $this->lastMessage = null;
+        $this->validateName($name);
+        $this->loadKeys();
+        $this->export($name.'.'.substr_replace(md5($name), '.sodium', -26), sodium_crypto_box_seal($value, $this->encryptionKey ?? sodium_crypto_box_publickey($this->decryptionKey)));
+        $this->lastMessage = sprintf('Secret "%s" encrypted in "%s"; you can commit it.', $name, $this->getPrettyPath(\dirname($this->pathPrefix).\DIRECTORY_SEPARATOR));
+    }
+
+    public function reveal(string $name): ?string
+    {
+        $this->lastMessage = null;
+        $this->validateName($name);
+
+        if (!file_exists($file = $this->pathPrefix.$name.'.'.substr_replace(md5($name), '.sodium', -26))) {
+            $this->lastMessage = sprintf('Secret "%s" not found in "%s".', $name, $this->getPrettyPath(\dirname($this->pathPrefix).\DIRECTORY_SEPARATOR));
+
+            return null;
+        }
+
+        $this->loadKeys();
+
+        if ('' === $this->decryptionKey) {
+            $this->lastMessage = sprintf('Secrets cannot be revealed as no decryption key was found in "%s".', $this->getPrettyPath(\dirname($this->pathPrefix).\DIRECTORY_SEPARATOR));
+
+            return null;
+        }
+
+        return sodium_crypto_box_seal_open(include $file, $this->decryptionKey);
+    }
+
+    public function remove(string $name): bool
+    {
+        $this->lastMessage = null;
+        $this->validateName($name);
+
+        if (!file_exists($file = $this->pathPrefix.$name.'.'.substr_replace(md5($name), '.sodium', -26))) {
+            $this->lastMessage = sprintf('Secret "%s" not found in "%s".', $name, $this->getPrettyPath(\dirname($this->pathPrefix).\DIRECTORY_SEPARATOR));
+
+            return false;
+        }
+
+        $this->lastMessage = sprintf('Secret "%s" removed from "%s".', $name, $this->getPrettyPath(\dirname($this->pathPrefix).\DIRECTORY_SEPARATOR));
+
+        return @unlink($file) || !file_exists($file);
+    }
+
+    public function list(bool $reveal = false): array
+    {
+        $this->lastMessage = null;
+        $secrets = [];
+        $regexp = sprintf('{^%s(\w++)\.[0-9a-f]{6}\.sodium$}D', preg_quote(basename($this->pathPrefix)));
+
+        foreach (scandir(\dirname($this->pathPrefix)) as $name) {
+            if (preg_match($regexp, $name, $m)) {
+                $secrets[$m[1]] = $reveal ? $this->reveal($m[1]) : null;
+            }
+        }
+
+        return $secrets;
+    }
+
+    private function loadKeys(): void
+    {
+        if (null !== $this->encryptionKey || '' !== $this->decryptionKey = (string) $this->decryptionKey) {
+            return;
+        }
+
+        if (file_exists($this->pathPrefix.'sodium.decrypt.private')) {
+            $this->decryptionKey = (string) include $this->pathPrefix.'sodium.decrypt.private';
+        }
+
+        if (file_exists($this->pathPrefix.'sodium.encrypt.public')) {
+            $this->encryptionKey = (string) include $this->pathPrefix.'sodium.encrypt.public';
+        } elseif ('' !== $this->decryptionKey) {
+            $this->encryptionKey = sodium_crypto_box_publickey($this->decryptionKey);
+        } else {
+            throw new \LogicException(sprintf('Encryption key not found in "%s".', \dirname($this->pathPrefix)));
+        }
+    }
+
+    private function export(string $file, string $data): void
+    {
+        $name = basename($this->pathPrefix.$file);
+        $data = str_replace('%', '\x', rawurlencode($data));
+        $data = sprintf("<?php // %s on %s\n\nreturn \"%s\";\n", $name, date('r'), $data);
+
+        if (false === file_put_contents($this->pathPrefix.$file, $data, LOCK_EX)) {
+            $e = error_get_last();
+            throw new \ErrorException($e['message'] ?? 'Failed to write secrets data.', 0, $e['type'] ?? E_USER_WARNING);
+        }
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php
index 05ffb61b70..f79897a6ba 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php
@@ -437,6 +437,12 @@ class ConfigurationTest extends TestCase
                 'enabled' => !class_exists(FullStack::class) && class_exists(Mailer::class),
             ],
             'error_controller' => 'error_controller',
+            'secrets' => [
+                'enabled' => true,
+                'vault_directory' => '%kernel.project_dir%/config/secrets/%kernel.environment%',
+                'local_dotenv_file' => '%kernel.project_dir%/.env.local',
+                'decryption_env_var' => 'base64:default::SYMFONY_DECRYPTION_SECRET',
+            ],
         ];
     }
 }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Secrets/DotenvVaultTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Secrets/DotenvVaultTest.php
new file mode 100644
index 0000000000..ba234349d7
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Secrets/DotenvVaultTest.php
@@ -0,0 +1,57 @@
+<?php
+
+namespace Symfony\Bundle\FrameworkBundle\Tests\Secrets;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Bundle\FrameworkBundle\Secrets\DotenvVault;
+use Symfony\Component\Dotenv\Dotenv;
+
+class DotenvVaultTest extends TestCase
+{
+    private $envFile;
+
+    protected function setUp(): void
+    {
+        $this->envFile = sys_get_temp_dir().'/sf_secrets.env.test';
+        @unlink($this->envFile);
+    }
+
+    protected function tearDown(): void
+    {
+        @unlink($this->envFile);
+    }
+
+    public function testGenerateKeys()
+    {
+        $vault = new DotenvVault($this->envFile);
+
+        $this->assertFalse($vault->generateKeys());
+        $this->assertSame('The dotenv vault doesn\'t encrypt secrets thus doesn\'t need keys.', $vault->getLastMessage());
+    }
+
+    public function testEncryptAndDecrypt()
+    {
+        $vault = new DotenvVault($this->envFile);
+
+        $plain = "plain\ntext";
+
+        $vault->seal('foo', $plain);
+
+        unset($_SERVER['foo_SECRET'], $_ENV['foo_SECRET']);
+        (new Dotenv(false))->load($this->envFile);
+
+        $decrypted = $vault->reveal('foo');
+        $this->assertSame($plain, $decrypted);
+
+        $this->assertSame(['foo' => null], $vault->list());
+        $this->assertSame(['foo' => $plain], $vault->list(true));
+
+        $this->assertTrue($vault->remove('foo'));
+        $this->assertFalse($vault->remove('foo'));
+
+        unset($_SERVER['foo_SECRET'], $_ENV['foo_SECRET']);
+        (new Dotenv(false))->load($this->envFile);
+
+        $this->assertSame([], $vault->list());
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Secrets/SodiumVaultTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Secrets/SodiumVaultTest.php
new file mode 100644
index 0000000000..2e25df9024
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Secrets/SodiumVaultTest.php
@@ -0,0 +1,64 @@
+<?php
+
+namespace Symfony\Bundle\FrameworkBundle\Tests\Secrets;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Bundle\FrameworkBundle\Secrets\SodiumVault;
+use Symfony\Component\Filesystem\Filesystem;
+
+class SodiumVaultTest extends TestCase
+{
+    private $secretsDir;
+
+    protected function setUp(): void
+    {
+        $this->secretsDir = sys_get_temp_dir().'/sf_secrets/test/';
+        (new Filesystem())->remove($this->secretsDir);
+    }
+
+    protected function tearDown(): void
+    {
+        (new Filesystem())->remove($this->secretsDir);
+    }
+
+    public function testGenerateKeys()
+    {
+        $vault = new SodiumVault($this->secretsDir);
+
+        $this->assertTrue($vault->generateKeys());
+        $this->assertFileExists($this->secretsDir.'/test.sodium.encrypt.public');
+        $this->assertFileExists($this->secretsDir.'/test.sodium.decrypt.private');
+
+        $encKey = file_get_contents($this->secretsDir.'/test.sodium.encrypt.public');
+        $decKey = file_get_contents($this->secretsDir.'/test.sodium.decrypt.private');
+
+        $this->assertFalse($vault->generateKeys());
+        $this->assertStringEqualsFile($this->secretsDir.'/test.sodium.encrypt.public', $encKey);
+        $this->assertStringEqualsFile($this->secretsDir.'/test.sodium.decrypt.private', $decKey);
+
+        $this->assertTrue($vault->generateKeys(true));
+        $this->assertStringNotEqualsFile($this->secretsDir.'/test.sodium.encrypt.public', $encKey);
+        $this->assertStringNotEqualsFile($this->secretsDir.'/test.sodium.decrypt.private', $decKey);
+    }
+
+    public function testEncryptAndDecrypt()
+    {
+        $vault = new SodiumVault($this->secretsDir);
+        $vault->generateKeys();
+
+        $plain = "plain\ntext";
+
+        $vault->seal('foo', $plain);
+
+        $decrypted = $vault->reveal('foo');
+        $this->assertSame($plain, $decrypted);
+
+        $this->assertSame(['foo' => null], $vault->list());
+        $this->assertSame(['foo' => $plain], $vault->list(true));
+
+        $this->assertTrue($vault->remove('foo'));
+        $this->assertFalse($vault->remove('foo'));
+
+        $this->assertSame([], $vault->list());
+    }
+}
diff --git a/src/Symfony/Bundle/FrameworkBundle/composer.json b/src/Symfony/Bundle/FrameworkBundle/composer.json
index d75499f3fa..e67a3c94bf 100644
--- a/src/Symfony/Bundle/FrameworkBundle/composer.json
+++ b/src/Symfony/Bundle/FrameworkBundle/composer.json
@@ -32,11 +32,13 @@
     "require-dev": {
         "doctrine/annotations": "~1.7",
         "doctrine/cache": "~1.0",
+        "paragonie/sodium_compat": "^1.8",
         "symfony/asset": "^3.4|^4.0|^5.0",
         "symfony/browser-kit": "^4.3|^5.0",
         "symfony/console": "^4.3.4|^5.0",
         "symfony/css-selector": "^3.4|^4.0|^5.0",
         "symfony/dom-crawler": "^4.3|^5.0",
+        "symfony/dotenv": "^4.3.6|^5.0",
         "symfony/polyfill-intl-icu": "~1.0",
         "symfony/form": "^4.3.4|^5.0",
         "symfony/expression-language": "^3.4|^4.0|^5.0",
@@ -69,7 +71,7 @@
         "symfony/asset": "<3.4",
         "symfony/browser-kit": "<4.3",
         "symfony/console": "<4.3",
-        "symfony/dotenv": "<4.2",
+        "symfony/dotenv": "<4.3.6",
         "symfony/dom-crawler": "<4.3",
         "symfony/http-client": "<4.4",
         "symfony/form": "<4.3",