Vulnerability Description
The Wishlist Member plugin for WordPress is vulnerable to Account Takeover via Insufficient Verification of Data Authenticity in versions up to and including 3.34.1. This is due to the wpm_register() function validating the registration cookie only against the GET reg parameter while accepting the POST mergewith and POST wpm_id parameters without verifying that the mergewith user ID references a temporary or incomplete registrant that is bound to the current registration transaction. This makes it possible for unauthenticated attackers to take over any existing WordPress account — including administrator accounts — by supplying an arbitrary user's numeric ID as the mergewith value, which causes wp_update_user() to overwrite the target account's username (additionally written via a direct $wpdb UPDATE), password, email address, first name, and last name with attacker-controlled values, while WordPress password and email change notification emails are explicitly suppressed. When wpm_id references a non-existent membership level, no role key is added to the update payload, causing wp_update_user() to preserve the target user's existing role — including administrator — making full privilege escalation a direct consequence of the takeover.
CVSS Score
CRITICAL
Related Weaknesses (CWE)
References
- https://wishlistmember.com/
- https://www.wordfence.com/threat-intel/vulnerabilities/id/84afe5a7-1bf4-4b83-bf7
FAQ
What is CVE-2026-12949?
CVE-2026-12949 is a vulnerability with a CVSS score of 9.8 (CRITICAL). The Wishlist Member plugin for WordPress is vulnerable to Account Takeover via Insufficient Verification of Data Authenticity in versions up to and including 3.34.1. This is due to the wpm_register() ...
How severe is CVE-2026-12949?
CVE-2026-12949 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-12949?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.