diff --git a/src/Symfony/Component/Mailer/composer.json b/src/Symfony/Component/Mailer/composer.json
index 31a9360564..5c4ad672a7 100644
--- a/src/Symfony/Component/Mailer/composer.json
+++ b/src/Symfony/Component/Mailer/composer.json
@@ -20,7 +20,7 @@
         "egulias/email-validator": "^2.0",
         "psr/log": "~1.0",
         "symfony/event-dispatcher": "^4.3",
-        "symfony/mime": "^4.3|^5.0"
+        "symfony/mime": "^4.3.3|^5.0"
     },
     "require-dev": {
         "symfony/amazon-mailer": "^4.4|^5.0",