Vulnerability 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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 128.6.0 |
| Mozilla | Thunderbird | < 128.6.0 |
Related Weaknesses (CWE)
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1929623Issue TrackingPermissions Required
- https://www.mozilla.org/security/advisories/mfsa2025-01/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-02/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-04/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-05/Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2025/01/msg00004.html
FAQ
What is CVE-2025-0240?
CVE-2025-0240 is a vulnerability with a CVSS score of 4.0 (MEDIUM). 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....
How severe is CVE-2025-0240?
CVE-2025-0240 has been rated MEDIUM with a CVSS base score of 4.0/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-0240?
Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox, Mozilla Thunderbird.