This emergency release introduces a new rule to block a cPanel & WHM Authentication Bypass related to CVE-2026-41940.
Key Findings
- CVE-2026-41940: A critical authentication bypass vulnerability in cPanel & WHM allows unauthenticated remote attackers to bypass authentication mechanisms and gain unauthorized administrative access to the web hosting control panel. This vulnerability affects the session validation logic, enabling attackers to craft malicious requests that circumvent normal authentication checks.
Impact
Successful exploitation allows unauthenticated attackers to gain administrative control over affected cPanel & WHM installations. This leads to complete server compromise, potential theft or manipulation of hosted data, and significant service disruption across managed environments.
We strongly recommend applying official vendor patches for cPanel & WHM immediately to address the underlying vulnerability.
| Ruleset | Rule ID | Legacy Rule ID | Description | Previous Action | New Action | Comments |
|---|---|---|---|---|---|---|
| Cloudflare Managed Ruleset | fb29b1b660864285a5ebac86eb2b9e2f | N/A | cPanel – Auth Bypass – CVE:CVE-2026-41940 | N/A | Block | This is a new detection. |
Source: Cloudflare
Latest Posts
- MC1455035: Power Pages Rolls Out Early Upgrade to Version 9.8.8.5 with Performance and Security Fixes
- MC1455050: Power Platform Adds GitHub Support for Source Code Integration with Enhanced APIs and Performance
- MC1455051: Dynamics 365 Customer Service and Contact Center Adds Workforce Alerts for Intraday Volume Spikes
- Workers, Access – You can now enable Access on a Worker or all Workers at once
