diff --git a/admin/framework/composer.json b/admin/framework/composer.json
index ea5e3ac9faa2..d2e787e5e035 100644
--- a/admin/framework/composer.json
+++ b/admin/framework/composer.json
@@ -17,7 +17,7 @@
     "require-dev": {
         "codeigniter/coding-standard": "^1.5",
         "fakerphp/faker": "^1.9",
-        "friendsofphp/php-cs-fixer": "~3.11.0",
+        "friendsofphp/php-cs-fixer": "~3.12.0",
         "mikey179/vfsstream": "^1.6",
         "nexusphp/cs-config": "^3.6",
         "phpunit/phpunit": "^9.1",
diff --git a/composer.json b/composer.json
index 8fca22ded575..99e3b68d96b6 100644
--- a/composer.json
+++ b/composer.json
@@ -17,7 +17,7 @@
     "require-dev": {
         "codeigniter/coding-standard": "^1.5",
         "fakerphp/faker": "^1.9",
-        "friendsofphp/php-cs-fixer": "~3.11.0",
+        "friendsofphp/php-cs-fixer": "~3.12.0",
         "mikey179/vfsstream": "^1.6",
         "nexusphp/cs-config": "^3.6",
         "nexusphp/tachycardia": "^1.0",
diff --git a/tests/_support/Log/Handlers/TestHandler.php b/tests/_support/Log/Handlers/TestHandler.php
index e20a32c2b0b6..82c893e271e9 100644
--- a/tests/_support/Log/Handlers/TestHandler.php
+++ b/tests/_support/Log/Handlers/TestHandler.php
@@ -47,8 +47,8 @@ public function __construct(array $config)
      * will stop. Any handlers that have not run, yet, will not
      * be run.
      *
-     * @param $level
-     * @param $message
+     * @param string $level
+     * @param string $message
      */
     public function handle($level, $message): bool
     {
diff --git a/tests/system/Config/MimesTest.php b/tests/system/Config/MimesTest.php
index cbd389882fcf..35d9c9819100 100644
--- a/tests/system/Config/MimesTest.php
+++ b/tests/system/Config/MimesTest.php
@@ -47,12 +47,8 @@ public function extensionsList()
 
     /**
      * @dataProvider extensionsList
-     *
-     * @param $expected
-     * @param $ext
-     * @param mixed $mime
      */
-    public function testGuessExtensionFromType($expected, $mime)
+    public function testGuessExtensionFromType(?string $expected, string $mime)
     {
         $this->assertSame($expected, Mimes::guessExtensionFromType($mime));
     }
@@ -85,11 +81,8 @@ public function mimesList()
 
     /**
      * @dataProvider mimesList
-     *
-     * @param mixed $expected
-     * @param mixed $ext
      */
-    public function testGuessTypeFromExtension($expected, $ext)
+    public function testGuessTypeFromExtension(?string $expected, string $ext)
     {
         $this->assertSame($expected, Mimes::guessTypeFromExtension($ext));
     }
diff --git a/tests/system/Validation/FormatRulesTest.php b/tests/system/Validation/FormatRulesTest.php
index 4cf445ee950d..fda3670344f7 100644
--- a/tests/system/Validation/FormatRulesTest.php
+++ b/tests/system/Validation/FormatRulesTest.php
@@ -411,9 +411,6 @@ public function stringProvider(): Generator
 
     /**
      * @dataProvider alphaProvider
-     *
-     * @param $str
-     * @param $expected
      */
     public function testAlpha(?string $str, bool $expected): void
     {