Ultimate Member <= 2.6.6 - Privilege Escalation via Arbitrary User Meta Updates

Incorrect Privilege Assignment
CVE CVE-2023-3460
CVSS Critical (9.8)
Publicly Published June 29, 2023
Last Updated January 22, 2024
Researcher Marc-Alexandre Montpas
Description

The Ultimate Member plugin for WordPress is vulnerable to privilege escalation in versions up to, and including, 2.6.6. This is due to the plugin using a predefined list of user meta keys that are banned which can be bypassed via a few method like adding slashes to the user meta key. This makes it possible for unauthenticated attackers to register on a site as an administrator.

References

1 affected software package

Software Type Plugin
Software Slug ultimate-member (view on wordpress.org)
Patched? Yes
Affected Version
  • <= 2.6.6
Patched Version
  • 2.6.7
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