Buffer overflow in Mozilla Firefox
CVE-2025-13027
Memory safety bugs present in Firefox 144 and Thunderbird 144. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 145 and Thunderbird 145.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.003 (23.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 23.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Mozilla Firefox — versions 145
- Mozilla Thunderbird — versions 145
Weakness classification (CWE)
References
- bugzilla.mozilla.org/buglist.cgi (Broken Link)
- www.mozilla.org/security/advisories/mfsa2025-87/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2025-90/
Frequently asked questions
- What is CVE-2025-13027?
- CVE-2025-13027 is a high-severity vulnerability in Mozilla Firefox, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.1/10. Published 2025-11-11.
- How severe is CVE-2025-13027?
- High severity. CVSS v3 base score is 8.1 out of 10.