CVE-2026-25411: Revision Manager TMC CSRF Vulnerability

CVE-2026-25411 Overview

CVE-2026-25411 is a Cross-Site Request Forgery (CSRF) vulnerability affecting the themastercut Revision Manager TMC plugin for WordPress. The flaw is present in all versions up to and including 2.8.22. An attacker can craft a malicious request that, when triggered by an authenticated user visiting an attacker-controlled page, performs unintended state-changing actions within the plugin. The issue is tracked under CWE-352 and was published to the National Vulnerability Database on 2026-02-19.

Critical Impact
A successful exploit allows an attacker to perform unauthorized actions on behalf of an authenticated WordPress user, resulting in limited integrity impact on the affected site.

Affected Products

themastercut Revision Manager TMC plugin (revision-manager-tmc)
All versions from initial release through 2.8.22
WordPress installations with the plugin active

Discovery Timeline

2026-02-19 - CVE-2026-25411 published to NVD
2026-04-15 - Last updated in NVD database

Technical Details for CVE-2026-25411

Vulnerability Analysis

The Revision Manager TMC plugin fails to validate the origin or authenticity of state-changing HTTP requests. Sensitive plugin actions do not verify a WordPress nonce or equivalent anti-CSRF token before processing. An attacker exploits this by hosting a malicious page or sending a link that issues forged requests to a vulnerable WordPress site. When an authenticated user with sufficient privileges loads the attacker's content, the browser submits the forged request along with valid session cookies.

The attack requires user interaction, which limits opportunistic exploitation. The impact is confined to integrity, with no direct confidentiality or availability consequences according to the published CVSS vector. The EPSS data indicates a low probability of exploitation at this time.

Root Cause

The root cause is the absence of CSRF protections on privileged plugin endpoints. WordPress provides wp_nonce_field() and check_admin_referer() helpers for this purpose, but the affected handlers in Revision Manager TMC do not enforce nonce verification before executing state-changing logic. This omission falls under CWE-352: Cross-Site Request Forgery.

Attack Vector

The vulnerability is exploited over the network. An attacker constructs an HTML page containing a form or fetch request targeting a vulnerable plugin endpoint on the victim's WordPress site. The attacker delivers the page through phishing, a malicious advertisement, or a compromised third-party site. When an authenticated administrator or editor visits the page, the browser automatically attaches authentication cookies, and the forged request executes plugin actions with the victim's privileges.

Technical details are available in the Patchstack CSRF Vulnerability Advisory.

Detection Methods for CVE-2026-25411

Indicators of Compromise

Unexpected modifications to post revisions or plugin settings without a corresponding admin session in WordPress audit logs.
HTTP POST requests to Revision Manager TMC endpoints with Referer headers pointing to external domains.
Administrative actions originating from sessions that immediately follow visits to untrusted external sites.

Detection Strategies

Inspect WordPress access logs for state-changing requests to revision-manager-tmc handlers that lack a valid _wpnonce parameter.
Correlate admin user activity with browser referrer chains to identify requests initiated from external origins.
Deploy a Web Application Firewall (WAF) rule that flags POST requests to plugin endpoints missing nonce tokens.

Monitoring Recommendations

Enable WordPress activity logging plugins to capture user actions, request sources, and parameter changes.
Forward web server logs to a centralized analytics platform for query against CSRF-style request patterns.
Alert on anomalous administrative actions performed outside of typical maintenance windows.

How to Mitigate CVE-2026-25411

Immediate Actions Required

Update Revision Manager TMC to a version later than 2.8.22 once the vendor publishes a patched release.
Restrict administrator and editor accounts to dedicated browsers or sessions that do not visit untrusted sites.
Review recent post revisions and plugin configuration changes for unauthorized modifications.

Patch Information

A fixed version beyond 2.8.22 should be applied as soon as it is published by themastercut. Monitor the Patchstack advisory for release availability and version details.

Workarounds

Deactivate the Revision Manager TMC plugin until a patched version is installed.
Enforce a WAF rule that requires a valid WordPress nonce on state-changing requests to the plugin's endpoints.
Require administrators to log out of WordPress before browsing external sites to reduce the active session attack window.

bash

# Example WAF rule: block POST requests to plugin endpoints missing a nonce parameter
SecRule REQUEST_METHOD "@streq POST" \
  "chain,id:1002641,phase:2,deny,status:403,msg:'Blocked CSRF attempt on Revision Manager TMC'"
  SecRule REQUEST_URI "@contains /wp-admin/admin.php?page=revision-manager-tmc" \
    "chain"
    SecRule &ARGS:_wpnonce "@eq 0"