CVE-2025-4087
4.8
MEDIUM
CVSS 3.1
EPSS 0.37%
Description
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.
How to fix CVE-2025-4087
To remediate CVE-2025-4087, upgrade the affected package to a fixed version below.
- —upgrade to 128.10.1esr-1~deb11u1 or later
- —upgrade to 1:128.10.1esr-1~deb11u1 or later
Is CVE-2025-4087 being exploited?
Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 128.10.1esr-1~deb11u1
- from 0, < 1:128.10.1esr-1~deb11u1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM4.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N |