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CVE-2026-41940: WebPros cPanel & WHM and WP2 (WordPress Squared) Missing Authentication for Critical Function Vulnerability
CVE-2026-41940 is rated critical with a CVSS v3.1 base score of 9.8 and affects WebPros cPanel & WHM and WP2 (WordPress Squared), along with 1 other product in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-04-30, which means exploitation in the wild has been observed.
Vulnerability description
cPanel and WHM versions after 11.40 contain an authentication bypass vulnerability in the login flow that allows unauthenticated remote attackers to gain unauthorized access to the control panel.
Severity breakdown
CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: None. No account or prior access is needed.
- User interaction: None. No action from any user is needed.
- Scope: Unchanged. Impact stays within the vulnerable component.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: High. Total loss of availability; the component can be shut down.
Underlying weakness
CWE-306: Missing Authentication for Critical Functionality
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
Affected products
- Cpanel: from 11.40 before 86.0.41; from 88.0.0 before 110.0.97; from 112.0.0 before 118.0.63; from 120.0.0 before 124.0.35; from 126.0.1 before 126.0.54; from 128.0.0 before 130.0.19; from 132.0.0 before 132.0.29; from 134.0.0 before 134.0.20; from 136.0.0 before 136.0.5
- Cpanel Whm: from 11.40 before 86.0.41; from 88.0.0 before 110.0.97; from 112.0.0 before 118.0.63; from 120.0.0 before 124.0.35; from 126.0.1 before 126.0.54; from 128.0.0 before 130.0.19; from 132.0.0 before 132.0.29; from 134.0.0 before 134.0.20; from 136.0.0 before 136.0.5
- Cpanel Wp Squared: before 136.1.7
References
- https://support.cpanel.net/hc/en-us/articles/40073787579671-cPanel-WHM-Security-Update-04-28-2026
- https://www.namecheap.com/status-updates/ongoing-critical-security-vulnerability-in-cpanel-april-28-2026
- https://www.vulncheck.com/advisories/cpanel-and-whm-authentication-bypass-via-login-flow
- https://labs.watchtowr.com/the-internet-is-falling-down-falling-down-falling-down-cpanel-whm-authentication-bypass-cve-2026-41940/
- https://github.com/watchtowrlabs/watchTowr-vs-cPanel-WHM-AuthBypass-to-RCE.py
- https://docs.cpanel.net/release-notes/release-notes
- https://docs.wpsquared.com/changelogs/versions/changelog/#13617
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-41940
- https://www.bleepingcomputer.com/news/security/critrical-cpanel-flaw-mass-exploited-in-sorry-ransomware-attacks/