CVE-2025-0240
4.0
MEDIUM
CVSS 3.1
EPSS 0.05%
Description
Parsing a JavaScript module as JSON could, under some circumstances, cause cross-compartment access, which may result in a use-after-free. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
How to fix CVE-2025-0240
To remediate CVE-2025-0240, upgrade the affected package to a fixed version below.
- Debian/firefox-esr—upgrade to 128.6.0esr-1~deb11u3 or later
- —upgrade to 1:128.6.0esr-1~deb11u1 or later
Is CVE-2025-0240 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 128.6.0esr-1~deb11u3
- from 0, < 1:128.6.0esr-1~deb11u1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM4.0 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |