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TI-2025-28488 Aliases CVE-2025-43921GHSA-ch5j-3wwr-pjvh

Incorrect authorization in GNU Mailman

Priority MEDIUM 63CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-863.

Summary

GNU Mailman 2.1.39, as bundled in cPanel (and WHM), allows unauthenticated attackers to create lists via the /mailman/create endpoint. NOTE: multiple third parties report that they are unable to reproduce this, regardless of whether cPanel or WHM is used.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00482 41st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
GNUMailman2.1.39—No fix listedCNA
  • Mailman VendorGNU Affected 2.1.39 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:gnu:mailman:*:*:*:*:*:*:*:*2.1.1 – 2.1.39VulnerableGNU
  • cpe:2.3:a:gnu:mailman:*:*:*:*:*:*:*:* Versions 2.1.1 – 2.1.39 Vulnerable ·GNU

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-43921
  2. 2026-10-03 Alias added: GHSA-ch5j-3wwr-pjvh

References

Exploit 1

Other 3

  • TI-2025-28486 Path traversal in GNU Mailman CVSS 3.1HIGH 7.5
  • TI-2025-28487 OS command injection in GNU Mailman CVSS 3.1HIGH 8.1
  • TI-2015-02450 Directory traversal vulnerability in GNU Mailman before 2.1.20, when not using a static… CVSS 2.0HIGH 7.6
  • TI-2002-00830 Cross-site scripting vulnerability in Mailman before 2.0.12 allows remote attackers to… CVSS 2.0HIGH 7.5
  • TI-2002-00374 Cross-site scripting vulnerabilities in Mailman before 2.0.11 allow remote attackers to… CVSS 2.0HIGH 7.5
  • TI-2016-06122 Cross-site request forgery (CSRF) vulnerability in the admin web interface in GNU Mailman… CVSS 3.0HIGH 8.8
See all 46 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences