Arbitrary Shortcode Execution in User Registration & Membership Plugin by WordPress
CVE-2026-92798

8.1HIGH

Key Information:

Vendor

WordPress
Status
User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder
Vendor
CVE Published:
17 October 2026

What is CVE-2026-92798?

The User Registration & Membership plugin for WordPress is susceptible to arbitrary shortcode execution due to inadequate input sanitization. This vulnerability affects versions up to and including 5.2.8, where user-controlled input from the HTTP_REFERER header is insufficiently sanitized before being processed. Specifically, the 'referrer_url' branch in the UR_Smart_Tags class allows attackers to inject shortcode delimiters into content restriction messages, enabling unauthorized execution of arbitrary shortcodes on restricted pages that utilize the {{referrer_url}} tag.

Affected Version(s)

User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder 0 <= 5.2.8

References

https://www.wordfence.com/threat-intel/vulnerabilities/id...
https://plugins.trac.wordpress.org/browser/user-registrat...
https://plugins.trac.wordpress.org/browser/user-registrat...

CVSS V3.1

Score:
8.1
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Passakorn Yookindee
.