diff --git a/src/Symfony/Component/Security/Core/Tests/User/ChainUserProviderTest.php b/src/Symfony/Component/Security/Core/Tests/User/ChainUserProviderTest.php
index aa9ade7020..aaf3e5291c 100644
--- a/src/Symfony/Component/Security/Core/Tests/User/ChainUserProviderTest.php
+++ b/src/Symfony/Component/Security/Core/Tests/User/ChainUserProviderTest.php
@@ -70,24 +70,49 @@ class ChainUserProviderTest extends TestCase
         $provider1 = $this->getProvider();
         $provider1
             ->expects($this->once())
-            ->method('refreshUser')
-            ->willThrowException(new UnsupportedUserException('unsupported'))
+            ->method('supportsClass')
+            ->willReturn(false)
         ;
 
         $provider2 = $this->getProvider();
         $provider2
+            ->expects($this->once())
+            ->method('supportsClass')
+            ->willReturn(true)
+        ;
+
+        $provider2
+            ->expects($this->once())
+            ->method('refreshUser')
+            ->willThrowException(new UnsupportedUserException('unsupported'))
+        ;
+
+        $provider3 = $this->getProvider();
+        $provider3
+            ->expects($this->once())
+            ->method('supportsClass')
+            ->willReturn(true)
+        ;
+
+        $provider3
             ->expects($this->once())
             ->method('refreshUser')
             ->willReturn($account = $this->getAccount())
         ;
 
-        $provider = new ChainUserProvider([$provider1, $provider2]);
+        $provider = new ChainUserProvider([$provider1, $provider2, $provider3]);
         $this->assertSame($account, $provider->refreshUser($this->getAccount()));
     }
 
     public function testRefreshUserAgain()
     {
         $provider1 = $this->getProvider();
+        $provider1
+            ->expects($this->once())
+            ->method('supportsClass')
+            ->willReturn(true)
+        ;
+
         $provider1
             ->expects($this->once())
             ->method('refreshUser')
@@ -95,6 +120,12 @@ class ChainUserProviderTest extends TestCase
         ;
 
         $provider2 = $this->getProvider();
+        $provider2
+            ->expects($this->once())
+            ->method('supportsClass')
+            ->willReturn(true)
+        ;
+
         $provider2
             ->expects($this->once())
             ->method('refreshUser')
@@ -109,6 +140,12 @@ class ChainUserProviderTest extends TestCase
     {
         $this->expectException('Symfony\Component\Security\Core\Exception\UnsupportedUserException');
         $provider1 = $this->getProvider();
+        $provider1
+            ->expects($this->once())
+            ->method('supportsClass')
+            ->willReturn(true)
+        ;
+
         $provider1
             ->expects($this->once())
             ->method('refreshUser')
@@ -116,6 +153,12 @@ class ChainUserProviderTest extends TestCase
         ;
 
         $provider2 = $this->getProvider();
+        $provider2
+            ->expects($this->once())
+            ->method('supportsClass')
+            ->willReturn(true)
+        ;
+
         $provider2
             ->expects($this->once())
             ->method('refreshUser')
@@ -173,6 +216,12 @@ class ChainUserProviderTest extends TestCase
     public function testAcceptsTraversable()
     {
         $provider1 = $this->getProvider();
+        $provider1
+            ->expects($this->once())
+            ->method('supportsClass')
+            ->willReturn(true)
+        ;
+
         $provider1
             ->expects($this->once())
             ->method('refreshUser')
@@ -180,6 +229,12 @@ class ChainUserProviderTest extends TestCase
         ;
 
         $provider2 = $this->getProvider();
+        $provider2
+            ->expects($this->once())
+            ->method('supportsClass')
+            ->willReturn(true)
+        ;
+
         $provider2
             ->expects($this->once())
             ->method('refreshUser')
diff --git a/src/Symfony/Component/Security/Core/User/ChainUserProvider.php b/src/Symfony/Component/Security/Core/User/ChainUserProvider.php
index 68bb91ec47..462a44e0cf 100644
--- a/src/Symfony/Component/Security/Core/User/ChainUserProvider.php
+++ b/src/Symfony/Component/Security/Core/User/ChainUserProvider.php
@@ -73,6 +73,10 @@ class ChainUserProvider implements UserProviderInterface, PasswordUpgraderInterf
 
         foreach ($this->providers as $provider) {
             try {
+                if (!$provider->supportsClass(\get_class($user))) {
+                    continue;
+                }
+
                 return $provider->refreshUser($user);
             } catch (UnsupportedUserException $e) {
                 // try next one
diff --git a/src/Symfony/Component/Security/Http/Firewall/ContextListener.php b/src/Symfony/Component/Security/Http/Firewall/ContextListener.php
index 69066552d7..d8a157e80b 100644
--- a/src/Symfony/Component/Security/Http/Firewall/ContextListener.php
+++ b/src/Symfony/Component/Security/Http/Firewall/ContextListener.php
@@ -201,12 +201,17 @@ class ContextListener extends AbstractListener
 
         $userNotFoundByProvider = false;
         $userDeauthenticated = false;
+        $userClass = \get_class($user);
 
         foreach ($this->userProviders as $provider) {
             if (!$provider instanceof UserProviderInterface) {
                 throw new \InvalidArgumentException(sprintf('User provider "%s" must implement "%s".', \get_class($provider), UserProviderInterface::class));
             }
 
+            if (!$provider->supportsClass($userClass)) {
+                continue;
+            }
+
             try {
                 $refreshedUser = $provider->refreshUser($user);
                 $newToken = clone $token;
@@ -263,7 +268,7 @@ class ContextListener extends AbstractListener
             return null;
         }
 
-        throw new \RuntimeException(sprintf('There is no user provider for user "%s".', \get_class($user)));
+        throw new \RuntimeException(sprintf('There is no user provider for user "%s".', $userClass));
     }
 
     private function safelyUnserialize(string $serializedToken)
diff --git a/src/Symfony/Component/Security/Http/Tests/Firewall/ContextListenerTest.php b/src/Symfony/Component/Security/Http/Tests/Firewall/ContextListenerTest.php
index a6f118f649..13ec17289a 100644
--- a/src/Symfony/Component/Security/Http/Tests/Firewall/ContextListenerTest.php
+++ b/src/Symfony/Component/Security/Http/Tests/Firewall/ContextListenerTest.php
@@ -253,7 +253,7 @@ class ContextListenerTest extends TestCase
     public function testIfTokenIsDeauthenticated()
     {
         $refreshedUser = new User('foobar', 'baz');
-        $tokenStorage = $this->handleEventWithPreviousSession([new NotSupportingUserProvider(), new SupportingUserProvider($refreshedUser)]);
+        $tokenStorage = $this->handleEventWithPreviousSession([new NotSupportingUserProvider(true), new NotSupportingUserProvider(false), new SupportingUserProvider($refreshedUser)]);
 
         $this->assertNull($tokenStorage->getToken());
     }
@@ -275,7 +275,7 @@ class ContextListenerTest extends TestCase
         $rememberMeServices = $this->createMock(RememberMeServicesInterface::class);
         $rememberMeServices->expects($this->once())->method('loginFail');
 
-        $tokenStorage = $this->handleEventWithPreviousSession([new NotSupportingUserProvider(), new SupportingUserProvider($refreshedUser)], null, $rememberMeServices);
+        $tokenStorage = $this->handleEventWithPreviousSession([new NotSupportingUserProvider(true), new NotSupportingUserProvider(false), new SupportingUserProvider($refreshedUser)], null, $rememberMeServices);
 
         $this->assertNull($tokenStorage->getToken());
     }
@@ -283,7 +283,7 @@ class ContextListenerTest extends TestCase
     public function testTryAllUserProvidersUntilASupportingUserProviderIsFound()
     {
         $refreshedUser = new User('foobar', 'baz');
-        $tokenStorage = $this->handleEventWithPreviousSession([new NotSupportingUserProvider(), new SupportingUserProvider($refreshedUser)], $refreshedUser);
+        $tokenStorage = $this->handleEventWithPreviousSession([new NotSupportingUserProvider(true), new NotSupportingUserProvider(false), new SupportingUserProvider($refreshedUser)], $refreshedUser);
 
         $this->assertSame($refreshedUser, $tokenStorage->getToken()->getUser());
     }
@@ -291,14 +291,14 @@ class ContextListenerTest extends TestCase
     public function testNextSupportingUserProviderIsTriedIfPreviousSupportingUserProviderDidNotLoadTheUser()
     {
         $refreshedUser = new User('foobar', 'baz');
-        $tokenStorage = $this->handleEventWithPreviousSession([new SupportingUserProvider(), new SupportingUserProvider($refreshedUser)], $refreshedUser);
+        $tokenStorage = $this->handleEventWithPreviousSession([new NotSupportingUserProvider(true), new NotSupportingUserProvider(false), new SupportingUserProvider($refreshedUser)], $refreshedUser);
 
         $this->assertSame($refreshedUser, $tokenStorage->getToken()->getUser());
     }
 
     public function testTokenIsSetToNullIfNoUserWasLoadedByTheRegisteredUserProviders()
     {
-        $tokenStorage = $this->handleEventWithPreviousSession([new NotSupportingUserProvider(), new SupportingUserProvider()]);
+        $tokenStorage = $this->handleEventWithPreviousSession([new NotSupportingUserProvider(true), new NotSupportingUserProvider(false), new SupportingUserProvider()]);
 
         $this->assertNull($tokenStorage->getToken());
     }
@@ -306,13 +306,13 @@ class ContextListenerTest extends TestCase
     public function testRuntimeExceptionIsThrownIfNoSupportingUserProviderWasRegistered()
     {
         $this->expectException('RuntimeException');
-        $this->handleEventWithPreviousSession([new NotSupportingUserProvider(), new NotSupportingUserProvider()]);
+        $this->handleEventWithPreviousSession([new NotSupportingUserProvider(false), new NotSupportingUserProvider(true)]);
     }
 
     public function testAcceptsProvidersAsTraversable()
     {
         $refreshedUser = new User('foobar', 'baz');
-        $tokenStorage = $this->handleEventWithPreviousSession(new \ArrayObject([new NotSupportingUserProvider(), new SupportingUserProvider($refreshedUser)]), $refreshedUser);
+        $tokenStorage = $this->handleEventWithPreviousSession(new \ArrayObject([new NotSupportingUserProvider(true), new NotSupportingUserProvider(false), new SupportingUserProvider($refreshedUser)]), $refreshedUser);
 
         $this->assertSame($refreshedUser, $tokenStorage->getToken()->getUser());
     }
@@ -338,7 +338,7 @@ class ContextListenerTest extends TestCase
             $this->assertNotEquals($event->getRefreshedToken()->getUser(), $user);
         });
 
-        $listener = new ContextListener($tokenStorage, [new NotSupportingUserProvider(), new SupportingUserProvider($refreshedUser)], 'context_key', null, $eventDispatcher);
+        $listener = new ContextListener($tokenStorage, [new NotSupportingUserProvider(true), new NotSupportingUserProvider(false), new SupportingUserProvider($refreshedUser)], 'context_key', null, $eventDispatcher);
         $listener(new RequestEvent($this->getMockBuilder(HttpKernelInterface::class)->getMock(), $request, HttpKernelInterface::MASTER_REQUEST));
 
         $this->assertNull($tokenStorage->getToken());
@@ -422,6 +422,14 @@ class ContextListenerTest extends TestCase
 
 class NotSupportingUserProvider implements UserProviderInterface
 {
+    /** @var bool */
+    private $throwsUnsupportedException;
+
+    public function __construct($throwsUnsupportedException)
+    {
+        $this->throwsUnsupportedException = $throwsUnsupportedException;
+    }
+
     public function loadUserByUsername($username): UserInterface
     {
         throw new UsernameNotFoundException();
@@ -429,7 +437,11 @@ class NotSupportingUserProvider implements UserProviderInterface
 
     public function refreshUser(UserInterface $user): UserInterface
     {
-        throw new UnsupportedUserException();
+        if ($this->throwsUnsupportedException) {
+            throw new UnsupportedUserException();
+        }
+
+        return $user;
     }
 
     public function supportsClass($class): bool
diff --git a/src/Symfony/Component/Yaml/Inline.php b/src/Symfony/Component/Yaml/Inline.php
index 40f2bfc8db..e5e0f2a4bd 100644
--- a/src/Symfony/Component/Yaml/Inline.php
+++ b/src/Symfony/Component/Yaml/Inline.php
@@ -679,6 +679,10 @@ class Inline
         $nextOffset = $i + $tagLength + 1;
         $nextOffset += strspn($value, ' ', $nextOffset);
 
+        if ('' === $tag && (!isset($value[$nextOffset]) || \in_array($value[$nextOffset], [']', '}', ','], true))) {
+            throw new ParseException(sprintf('Using the unquoted scalar value "!" is not supported. You must quote it.', $value), self::$parsedLineNumber + 1, $value, self::$parsedFilename);
+        }
+
         // Is followed by a scalar and is a built-in tag
         if ('' !== $tag && (!isset($value[$nextOffset]) || !\in_array($value[$nextOffset], ['[', '{'], true)) && ('!' === $tag[0] || 'str' === $tag || 'php/const' === $tag || 'php/object' === $tag)) {
             // Manage in {@link self::evaluateScalar()}
diff --git a/src/Symfony/Component/Yaml/Tests/InlineTest.php b/src/Symfony/Component/Yaml/Tests/InlineTest.php
index 0f8f8f8b94..0f46f75ee7 100644
--- a/src/Symfony/Component/Yaml/Tests/InlineTest.php
+++ b/src/Symfony/Component/Yaml/Tests/InlineTest.php
@@ -737,4 +737,69 @@ class InlineTest extends TestCase
             'negative octal number' => [-28, '-034'],
         ];
     }
+
+    /**
+     * @dataProvider unquotedExclamationMarkThrowsProvider
+     */
+    public function testUnquotedExclamationMarkThrows(string $value)
+    {
+        $this->expectException(ParseException::class);
+        $this->expectExceptionMessageRegExp('/^Using the unquoted scalar value "!" is not supported\. You must quote it at line 1 \(near "/');
+
+        Inline::parse($value);
+    }
+
+    public function unquotedExclamationMarkThrowsProvider()
+    {
+        return [
+            ['!'],
+            ['! '],
+            ['!  '],
+            [' ! '],
+            ['[!]'],
+            ['[! ]'],
+            ['[!  ]'],
+            ['[!, "foo"]'],
+            ['["foo", !, "ccc"]'],
+            ['{foo: !}'],
+            ['{foo:     !}'],
+            ['{foo: !, bar: "ccc"}'],
+            ['{bar: "ccc", foo: ! }'],
+            ['!]]]'],
+            ['!}'],
+            ['!,}foo,]'],
+            ['! [!]'],
+        ];
+    }
+
+    /**
+     * @dataProvider quotedExclamationMarkProvider
+     */
+    public function testQuotedExclamationMark($expected, string $value)
+    {
+        $this->assertSame($expected, Inline::parse($value));
+    }
+
+    // This provider should stay consistent with unquotedExclamationMarkThrowsProvider
+    public function quotedExclamationMarkProvider()
+    {
+        return [
+            ['!', '"!"'],
+            ['! ', '"! "'],
+            [' !', '" !"'],
+            [' ! ', '" ! "'],
+            [['!'], '["!"]'],
+            [['!  '], '["!  "]'],
+            [['!', 'foo'], '["!", "foo"]'],
+            [['foo', '!', 'ccc'], '["foo", "!", "ccc"]'],
+            [['foo' => '!'], '{foo: "!"}'],
+            [['foo' => '    !'], '{foo: "    !"}'],
+            [['foo' => '!', 'bar' => 'ccc'], '{foo: "!", bar: "ccc"}'],
+            [['bar' => 'ccc', 'foo' => '! '], '{bar: "ccc", foo: "! "}'],
+            ['!]]]', '"!]]]"'],
+            ['!}', '"!}"'],
+            ['!,}foo,]', '"!,}foo,]"'],
+            [['!'], '! ["!"]'],
+        ];
+    }
 }