diff --git a/composer.json b/composer.json
index 343e7c6..fa1febe 100644
--- a/composer.json
+++ b/composer.json
@@ -23,7 +23,7 @@
     },
     "require-dev": {
         "ext-json": "*",
-        "phpunit/phpunit": "^9.1.4"
+        "phpunit/phpunit": "^9.5.7"
     },
     "config": {
         "preferred-install": "dist",