Security readout for executives and security teams
Plain-English summary
A WordPress membership plugin allowed logged-in users with Contributor-level access to change site-wide content restriction rules. This could expose members-only content or block legitimate access. It is not an anonymous attack and is rated medium severity, but it matters for sites relying on paid memberships or restricted content.
Executive priority
Treat as a timely remediation item for membership, subscription, or gated-content sites. Prioritize sites with many contributors or paid content. It is not currently evidenced as actively exploited, but business impact can include lost revenue, privacy issues, or customer access disruption.
Technical view
CVE-2026-4056 is a missing authorization issue in User Registration & Membership versions 5.0.1 through 5.1.4. REST API endpoints for content access rules used an `edit_posts` capability check instead of an administrator-level check, allowing Contributor+ users to list, create, modify, toggle, duplicate, or delete restriction rules.
Likely exposure
Exposure is limited to WordPress sites running the User Registration & Membership plugin versions 5.0.1 through 5.1.4, especially where non-administrators have Contributor, Author, or Editor accounts. Sites without untrusted authenticated users have lower practical exposure.
Exploitation context
The CVE is not listed in KEV, and the provided sources do not report active exploitation. Exploitation requires a valid authenticated account with Contributor-level access or higher. The impact is unauthorized manipulation of access rules, affecting confidentiality and integrity of restricted content.
Researcher notes
The CVE description and Wordfence reference identify versions 5.0.1 through 5.1.4. CVE affected metadata in the bundle is sparse, so confirm against vendor records. The referenced WordPress Trac changeset appears related to permission-check remediation, but no exploit activity is cited.
Mitigation direction
- Identify all WordPress sites using this plugin.
- Do not run versions 5.0.1 through 5.1.4 in production.
- Check vendor or WordPress plugin guidance for the fixed release.
- Restrict Contributor+ accounts to trusted users until remediated.
- Review membership and content restriction settings after updating.
Validation and detection
- Inventory plugin versions across WordPress sites.
- Confirm whether any site runs versions 5.0.1 through 5.1.4.
- Review users with Contributor, Author, or Editor roles.
- Audit recent content access rule changes for unexpected modifications.
- Verify remediation against vendor release notes or code changes.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-862: Authorization and privilege behavior lookup
Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-4056 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N2.82.5Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.4MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/7bb5a5a2-9644-4850-a5f9-7c925af000c8?source=cveCVE reference
- 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#L116CVE reference
- https://plugins.trac.wordpress.org/browser/user-registration/trunk/modules/content-restriction/includes/RestApi/controllers/version1/class-urcr-content-access-rules.php#L116CVE reference
- https://plugins.trac.wordpress.org/changeset/3485702/user-registration/trunk/modules/content-restriction/includes/RestApi/controllers/version1/class-urcr-content-access-rules.phpCVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Missing Authorization
Missing Authorization represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.