CVE-2026-41940: WebPros cPanel & WHM and WP2 (WordPress Squared) Missing Authentication for Critical Function Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 30 Apr 2026, 1 day after the CVE record was published.

How likely is exploitation in the next 30 days?

98.5%

EPSS score, percentile 99.9 of all scored records

How severe?

9.3 Critical

CVSS v4.0 base score, given by the CNA

What should I do?

CISA deadline 3 May 2026. Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Advisories and patches (3)

Which versions are affected?

Affected

• from 11.40.0.0 to before 11.86.0.41
• from 11.88.0.0 to before 11.94.0.28
• from 11.96.0.0 to before 11.102.0.39
• from 11.104.0.0 to before 11.110.0.97
• from 11.112.0.0 to before 11.118.0.63
• from 11.120.0.0 to before 11.124.0.35

and 17 more in the table below

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

CISA due date for this action: 3 May 2026.

Advisories and patches

• support.cpanel.net (Vendor advisory, Patch)
• docs.cpanel.net (Release notes)
• docs.wpsquared.com (Release notes)

Linked from CISA's catalog entry

• https://support.cpanel.net/hc/en-us/articles/40073787579671-cPanel-WHM-Security-Update-04-28-2026
• https://docs.cpanel.net/release-notes/release-notes/
• https://docs.wpsquared.com/changelogs/versions/changelog/#13617
• https://nvd.nist.gov/vuln/detail/CVE-2026-41940"

Affected products and versions

As listed in the CVE record.

Versions not listed are: affected.

Versions not listed are: unaffected.

Versions not listed are: affected.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

WebPros cPanel & WHM (WebHost Manager) and WP2 (WordPress Squared) contain an authentication bypass vulnerability in the login flow that allows unauthenticated remote attackers to gain unauthorized access to the control panel.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

• CISA added CVE-2026-41940 to its Known Exploited Vulnerabilities (KEV) catalog on 30 Apr 2026.
• CISA marks it as known to be used in ransomware campaigns.
• The due date CISA sets for the required action is 3 May 2026.
• The CVE record was published on 29 Apr 2026, 1 day before it was added to KEV.
• The CVE record carries a CVSS v4.0 base score of 9.3 (Critical), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 98.5% (percentile 99.9), as of 28 Oct 2026.
• CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

WebPros cPanel and WHM Authentication Bypass via Login Flow

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.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

• CWE-306: Missing Authentication for Critical Function

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

References

• namecheap.com (Third-party advisory)
• vulncheck.com (Third-party advisory)