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TI-2025-28487 Aliases CVE-2025-43920GHSA-35m2-m3ch-fgh4

OS command injection in GNU Mailman

Priority HIGH 68CWE-78Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-78.

Summary

GNU Mailman 2.1.39, as bundled in cPanel (and WHM), in certain external archiver configurations, allows unauthenticated attackers to execute arbitrary OS commands via shell metacharacters in an email Subject line. 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 0.00602 49th 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
No
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-2025-43920
  2. 2026-10-03 Alias added: GHSA-35m2-m3ch-fgh4

References

Exploit 1

Other 3

  • TI-2025-28486 Path traversal in GNU Mailman CVSS 3.1HIGH 7.5
  • TI-2025-28488 Incorrect authorization in GNU Mailman CVSS 3.1MEDIUM 5.3
  • 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