fixed path traversal by santize checking fiilename

CHANGELOG.md

@@ -6,6 +6,7 @@
 1. [](#bugfix)
    * Fixed some multibyte issues in Inflector class [#732](https://github.com/getgrav/grav/issues/732)
    * Fallback to page modified date if Page date provided is invalid and can't be parsed [getgrav/grav-plugin-admin#2394](https://github.com/getgrav/grav-plugin-admin/issues/2394)
+   * Fixed a path traversal vulnerability with file uploads [GHSA-m7hx-hw6h-mqmc](https://github.com/getgrav/grav/security/advisories/GHSA-m7hx-hw6h-mqmc)
 
 # v1.7.44
 ## 01/05/2024

system/src/Grav/Common/Utils.php

@@ -989,6 +989,8 @@ public static function checkFilename($filename): bool
             || strtr($filename, "\t\v\n\r\0\\/", '_______') !== $filename
             // Filename should not start or end with dot or space.
             || trim($filename, '. ') !== $filename
+            // Filename should not contain path traversal
+            || str_replace('..', '', $filename) !== $filename
             // File extension should not be part of configured dangerous extensions
             || in_array($extension, $dangerous_extensions)
         );