What the vulnerability does
01Description
The wpForo Forum plugin for WordPress is vulnerable to Arbitrary File Deletion in versions up to and including 3.0.5. This is due to two compounding flaws: the Members::update() method does not validate or restrict the value of file-type custom profile fields, allowing authenticated users to store an arbitrary path instead of a legitimate upload path; and the wpforo_fix_upload_dir() sanitization function in ucf_file_delete() only remaps paths that match the expected pattern, and it is passed directly to the unlink() function. This makes it possible for authenticated attackers, with subscriber-level access and above, to delete arbitrary files on the server, which can easily lead to remote code execution when the right file is deleted (such as wp-config.php). Note: The vulnerability requires a file custom field, which requires the wpForo - User Custom Fields addon plugin.
Explanation of Vulnerability in Simple Terms
02Summary
wpForo Forum versions 3.0.5 and earlier contain a path traversal vulnerability that allows authenticated users to modify or delete files on the server. An attacker with low-level forum access can craft requests to access files outside the intended directory, potentially compromising site integrity and availability. Update to a version newer than 3.0.5 to resolve this issue.
What an attacker can do
03Attacker Capabilities
Modify or delete files on the server by traversing outside the intended directory.
Potential impact on your site
04Site Impact
Forum files and potentially other site files can be altered or removed by authenticated attackers, disrupting service.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege forum account; no user interaction required.
Key dates
06Disclosure timeline
April 20, 2026
CVE published
April 21, 2026
Record updated
