Directory Listings WordPress Plugin - uListing Missing Authorization Vulnerability Allowing Arbitrary Post Meta Update and PHP Object Injection

A vulnerability exists in the Directory Listings WordPress plugin, specifically in the uListing plugin, versions through 2.2.0. The issue arises from a missing capability check on the 'stm_listing_ajax' AJAX action, allowing authenticated attackers with subscriber-level access and above to unauthorizedly modify post meta data and inject PHP objects that could be unserialized. Although a capability check was introduced in version 2.1.8, the vulnerability related to unserialization remains unaddressed.

Impact

Exploitation of this vulnerability could lead to unauthorized data modification and PHP object injection, allowing for potential execution of arbitrary PHP code if the injected objects are crafted accordingly.