CVE-2025-5269
8.1
HIGH
CVSS 3.1
EPSS 0.43%
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.
How to fix CVE-2025-5269
To remediate CVE-2025-5269, upgrade the affected package to a fixed version below.
- Debian/firefox-esr—upgrade to 128.11.0esr-1~deb11u1 or later
- —upgrade to 1:128.11.0esr-1~deb11u1 or later
Is CVE-2025-5269 being exploited?
Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 128.11.0esr-1~deb11u1
- from 0, < 1:128.11.0esr-1~deb11u1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |