CVE intelligence and bounded remediation

CVE-2025-43919 — Gnu Mailman security vulnerability

High CVSS 7.5

GNU Mailman 2.1.39, as bundled in cPanel (and WHM), allows unauthenticated attackers to read arbitrary files via ../ directory traversal at /mailman/private/mailman (aka the private archive authentication endpoint) via the username parameter. NOTE: multiple third parties report that they are unable to reproduce this, regardless of whether cPanel or WHM is used.

Severity
High
CVSS
7.5 (3.1)
Published
2025-04-20
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-24, CWE-22

Affected products

  • gnu / mailman

Matched remediation archetype

Path traversal, unsafe upload, and file handling

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace untrusted filenames, archive entries, URLs, and path segments into read, write, include, extraction, and upload operations.
  • Identify filesystem roots, mount permissions, symbolic-link behavior, archive handling, and whether uploaded content is web-accessible or executable.
  • Review canonicalization and containment checks across supported operating systems and storage backends.

Remediate safely

  • Generate server-side storage identifiers and resolve paths beneath a fixed root using filesystem-aware containment checks.
  • Reject absolute, parent-relative, alternate-separator, device, link, and archive entries that escape the intended root.
  • Store uploads outside executable or served paths, validate type and size, and use private atomic temporary files.

Authoritative sources

Complete CVE record and remediation plan

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