diff --git a/src/Symfony/Component/Validator/Constraints/FileValidator.php b/src/Symfony/Component/Validator/Constraints/FileValidator.php
index e2b97b03ae204..e4e02c80fd18b 100644
--- a/src/Symfony/Component/Validator/Constraints/FileValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/FileValidator.php
@@ -171,7 +171,7 @@ public function validate(mixed $value, Constraint $constraint)
         $mimeTypes = (array) $constraint->mimeTypes;
 
         if ($constraint->extensions) {
-            $fileExtension = pathinfo($path, \PATHINFO_EXTENSION);
+            $fileExtension = pathinfo($basename, \PATHINFO_EXTENSION);
 
             $found = false;
             $normalizedExtensions = [];
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/FileValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/FileValidatorTest.php
index 1fd0c3857967d..c749480b87e49 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/FileValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/FileValidatorTest.php
@@ -640,5 +640,22 @@ public function testExtensionTypesIncoherent()
             ->assertRaised();
     }
 
+    public function testUploadedFileExtensions()
+    {
+        $file = new UploadedFile(__DIR__.'/Fixtures/bar', 'bar.txt', 'text/plain', \UPLOAD_ERR_OK, true);
+
+        try {
+            $file->getMimeType();
+        } catch (\LogicException $e) {
+            $this->markTestSkipped('Guessing the mime type is not possible');
+        }
+
+        $constraint = new File(mimeTypesMessage: 'myMessage', extensions: ['txt']);
+
+        $this->validator->validate($file, $constraint);
+
+        $this->assertNoViolation();
+    }
+
     abstract protected function getFile($filename);
 }