Medium severity · published Mar 23, 2026
CVE-2026-4056
User Registration & Membership <= 5.1.4 - Missing Authorization to Authenticated (Contributor+) Content Access Rule Manipulation
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
The User Registration & Membership plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the Content Access Rules REST API endpoints in versions 5.0.1 through 5.1.4. This is due to the `check_permissions()` method only checking for `edit_posts` capability instead of an administrator-level capability. This makes it possible for authenticated attackers, with Contributor-level access and above, to list, create, modify, toggle, duplicate, and delete site-wide content restriction rules, potentially exposing restricted content or denying legitimate user access.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
Affected product
UR
User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder
wpeverest
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4056
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-4056
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/user-registration/tags/5.1.1/modules/content-restriction/includes/RestApi/controllers/version1/class-urcr-content-access-rules.php#L116
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/user-registration/trunk/modules/content-restriction/includes/RestApi/controllers/version1/class-urcr-content-access-rules.php#L116
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/changeset/3485702/user-registration/trunk/modules/content-restriction/includes/RestApi/controllers/version1/class-urcr-content-access-rules.php
www.wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/7bb5a5a2-9644-4850-a5f9-7c925af000c8?source=cve
More from User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder
9.9
CVE-2023-3342
User Registration <= 3.0.2 - Authenticated (Subscriber+) Arbitrary File Upload
9.8
CVE-2026-1492
User Registration & Membership <= 5.1.2 - Unauthenticated Privilege Escalation via Membership Registration
8.8
CVE-2024-2417
User Registration – Custom Registration Form, Login Form, and User Profile WordPress Plugin <= 3.1.5 - Missing Authorization to Authenticated (Subscriber+) Privilege Escalation
8.8
CVE-2023-3343
User Registration <= 3.0.1 - Authenticated (Subscriber+) PHP Object Injection
8.1
CVE-2026-92798
User Registration & Membership <= 5.2.8 - Authenticated (Subscriber+) Arbitrary Shortcode Execution via Referer Header via 'referrer_url' Smart Tag