CVE-2026-41940 — cPanel and WHM versions after 11.40 contain an authentication bypass vulnerability in the login flow that allows unauthe

Summary

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.

Assessment

• CVE: CVE-2026-41940
• CVSS base score: 9.3
• Vector: CVSS:4.0\/AV:N\/AC:L\/AT:N\/PR:N\/UI:N\/VC:H\/VI:H\/VA:H\/SC:N\/SI:N\/SA:N\/E:X\/CR:X\/IR:X\/AR:X\/MAV:X\/MAC:X\/MAT:X\/MPR:X\/MUI:X\/MVC:X\/MVI:X\/MVA:X\/MSC:X\/MSI:X\/MSA:X\/S:X\/AU:X\/R:X\/V:X\/RE:X\/U:X
• Source: [NVD record](https:\/\/nvd.nist.gov\/vuln\/detail\/CVE-2026-41940)

References

• [docs.cpanel.net](https:\/\/docs.cpanel.net\/release-notes\/release-notes)
• [docs.wpsquared.com](https:\/\/docs.wpsquared.com\/changelogs\/versions\/changelog\/#13617)
• [support.cpanel.net](https:\/\/support.cpanel.net\/hc\/en-us\/articles\/40073787579671-cPanel-WHM-Security-Update-04-28-2026)
• [www.namecheap.com](https:\/\/www.namecheap.com\/status-updates\/ongoing-critical-security-vulnerability-in-cpanel-april-28-2026)
• [www.vulncheck.com](https:\/\/www.vulncheck.com\/advisories\/cpanel-and-whm-authentication-bypass-via-login-flow)
• [labs.watchtowr.com](https:\/\/labs.watchtowr.com\/the-internet-is-falling-down-falling-down-falling-down-cpanel-whm-authentication-bypass-cve-2026-41940\/)

Actions

• Verify affected systems in inventory
• Apply the vendor patch during a maintenance window
• Restrict access at the network layer until the patch is applied