CVE-2025-4087

A vulnerability was identified in Thunderbird where XPath parsing could trigger undefined behavior due to missing null checks during attribute access. This could lead to out-of-bounds read access and potentially, memory corruption. This vulnerability was fixed in Firefox 138, Firefox ESR 128.10, Thunderbird 138, and Thunderbird 128.10.

Score

CVSS 3.1 4.8 Medium

Status

Modified - security@mozilla.org

Published

2025-04-29

Last modified

2026-10-05

Weaknesses

CWE-125

Affected products

• Firefox (Mozilla)
• Thunderbird (Mozilla)

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1952465
• https://www.mozilla.org/security/advisories/mfsa2025-28/
• https://www.mozilla.org/security/advisories/mfsa2025-29/
• https://www.mozilla.org/security/advisories/mfsa2025-31/
• https://www.mozilla.org/security/advisories/mfsa2025-32/
• https://lists.debian.org/debian-lts-announce/2025/05/msg00024.html