- $imageData = $this->getAvatarImageData($avatarUrl, $accessToken);
- $avatar = $this->createAvatarImageFromData($user, $imageData, 'png');
+ $imageData = $this->getAvatarImageData($avatarUrl);
+
+ $mime = (new WebSafeMimeSniffer())->sniff($imageData);
+ [$format, $type] = explode('/', $mime, 2);
+ if ($format !== 'image' || ImageService::isExtensionSupported($type)) {
+ return;
+ }
+
+ $avatar = $this->createAvatarImageFromData($user, $imageData, $type);