What is CVE-2026-41940?

CVE-2026-41940 is a critical-severity vulnerability in Cpanel, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-04-29.

How severe is CVE-2026-41940?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2026-41940 known to be exploited?

Yes. CVE-2026-41940 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-04-30), indicating it is being actively exploited. 74 public proof-of-concept repositories are indexed.

Auth bypass in Cpanel

CVE-2026-41940

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.

Vulnerability class: Broken Authentication

EPSS: 0.908 (99.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Cpanel
Cpanel Whm
Cpanel Wp_squared
Webpros Cpanel — versions 11.104.0.0, 11.112.0.0, 11.120.0.0
Webpros Whm — versions 11.104.0.0, 11.112.0.0, 11.120.0.0
Webpros Wp Squared — versions 11.136.1.7

Weakness classification (CWE)

CWE-306 — Missing Authentication for Critical Function

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2026-04-30. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2026-05-03.

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Known ransomware campaign use: yes.

Public proof-of-concept exploits

References

disclosure@vulncheck.com (vendor-advisory, patch, Vendor Advisory)
disclosure@vulncheck.com (release-notes, Release Notes)
disclosure@vulncheck.com (release-notes, Release Notes)
disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)
disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)
af854a3a-2127-422b-91ae-364da2661108 (Exploit, Third Party Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Press/Media Coverage)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (Exploit, Third Party Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2026-41940?: CVE-2026-41940 is a critical-severity vulnerability in Cpanel, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-04-29.
How severe is CVE-2026-41940?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-41940 known to be exploited?: Yes. CVE-2026-41940 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-04-30), indicating it is being actively exploited. 74 public proof-of-concept repositories are indexed.