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.
CISA Known Exploited Vulnerability
Date added 2026-04-30 | Due date 2026-05-03
Known Ransomware Campaign(s)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Problem types
CWE-306 Missing Authentication for Critical Function
Product status
11.40.0.0 (custom) before 11.86.0.41
11.88.0.0 (custom) before 11.94.0.28
11.96.0.0 (custom) before 11.102.0.39
11.104.0.0 (custom) before 11.110.0.97
11.112.0.0 (custom) before 11.118.0.63
11.120.0.0 (custom) before 11.124.0.35
11.126.0.0 (custom) before 11.126.0.54
11.128.0.0 (custom) before 11.130.0.19
11.132.0.0 (custom) before 11.132.0.29
11.134.0.0 (custom) before 11.134.0.20
11.136.0.0 (custom) before 11.136.0.5
11.136.1.7 (custom)
11.40.0.0 (custom) before 11.86.0.41
11.88.0.0 (custom) before 11.94.0.28
11.96.0.0 (custom) before 11.102.0.39
11.104.0.0 (custom) before 11.110.0.97
11.112.0.0 (custom) before 11.118.0.63
11.120.0.0 (custom) before 11.124.0.35
11.126.0.0 (custom) before 11.126.0.54
11.128.0.0 (custom) before 11.130.0.19
11.132.0.0 (custom) before 11.132.0.29
11.134.0.0 (custom) before 11.134.0.20
11.136.0.0 (custom) before 11.136.0.5
References
github.com/...s/watchTowr-vs-cPanel-WHM-AuthBypass-to-RCE.py
www.cisa.gov/...erabilities-catalog?field_cve=CVE-2026-41940
www.bleepingcomputer.com/...ted-in-sorry-ransomware-attacks/
labs.watchtowr.com/...-authentication-bypass-cve-2026-41940/
support.cpanel.net/...-cPanel-WHM-Security-Update-04-28-2026
docs.cpanel.net/release-notes/release-notes
docs.wpsquared.com/changelogs/versions/changelog/
www.namecheap.com/...y-vulnerability-in-cpanel-april-28-2026
www.vulncheck.com/...hm-authentication-bypass-via-login-flow