Buffer overflow in Mozilla Firefox
CVE-2023-6856
The WebGL `DrawElementsInstanced` method was susceptible to a heap buffer overflow when used on systems with the Mesa VM driver. This issue could allow an attacker to perform remote code execution and sandbox escape. This vulnerability affects Firefox ESR < 115.6, Thunderbird < 115.6, and Firefox < 121.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.206 (97.5th percentile), scored .
Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 97th percentile — 97.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.206 · newest: 0.206 · change: 0.000
Affected products
- Mozilla Firefox — versions unspecified
- Mozilla Firefox Esr — versions unspecified
- Mozilla Firefox Esr
- Mozilla Thunderbird — versions unspecified
- Debian Linux — versions 10.0, 11.0, 12.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking)
- www.mozilla.org/security/advisories/mfsa2023-54/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2023-55/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2023-56/ (Vendor Advisory)
- www.debian.org/security/2023/dsa-5581 (Third Party Advisory)
- www.debian.org/security/2023/dsa-5582 (Third Party Advisory)
- lists.debian.org/debian-lts-announce/2023/12/msg00020.html (Mailing List, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2023/12/msg00021.html (Mailing List, Third Party Advisory)
- security.gentoo.org/glsa/202401-10 (Third Party Advisory)
Frequently asked questions
- What is CVE-2023-6856?
- CVE-2023-6856 is a high-severity vulnerability in Mozilla Firefox, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2023-12-19.
- How severe is CVE-2023-6856?
- High severity. CVSS v3 base score is 8.8 out of 10.
- Is CVE-2023-6856 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.