CVE-2026-41940

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.

Scoring

• CVSS: 9.8 (CRITICAL, 3.1)
• EPSS exploitation probability: Not yet available
• EPSS percentile: Not yet available

CISA KEV status

• Added to KEV: 2026-04-30
• Remediation due date: 2026-05-03
• Known ransomware campaign use: Known

Weakness types (CWE)

• CWE-306

References

• https://docs.cpanel.net/release-notes/release-notes
• https://docs.wpsquared.com/changelogs/versions/changelog/#13617
• 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://www.bleepingcomputer.com/news/security/critrical-cpanel-flaw-mass-exploited-in-sorry-ransomware-attacks/
• https://github.com/watchtowrlabs/watchTowr-vs-cPanel-WHM-AuthBypass-to-RCE.py
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-41940

More from WebPros

• No other tracked CVEs for this vendor yet.