High severity8.1NVD Advisory· Published May 27, 2025· Updated Apr 13, 2026

CVE-2025-5269

Description

Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox ESR 128.11 and Thunderbird 128.11.

Affected products

Mozilla Corporation/Firefox
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
Range: <128.11.0
Mozilla Corporation/Thunderbird
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
Range: <128.11.0

Patches

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

www.mozilla.org/security/advisories/mfsa2025-44/nvdVendor Advisory
bugzilla.mozilla.org/show_bug.cginvdPermissions Required
lists.debian.org/debian-lts-announce/2025/05/msg00043.htmlnvd
lists.debian.org/debian-lts-announce/2025/05/msg00046.htmlnvd
www.mozilla.org/security/advisories/mfsa2025-46/nvd

News mentions

No linked articles in our index yet.

cvss	0.526
epss	0.000
exploit	0.000
kev	0.000
patch	0.000
ransomware	0.000