Use After Free in Mozilla Firefox
CVE-2023-5171
During Ion compilation, a Garbage Collection could have resulted in a use-after-free condition, allowing an attacker to write two NUL bytes, and cause a potentially exploitable crash. This vulnerability affects Firefox < 118, Firefox ESR < 115.3, and Thunderbird < 115.3.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.011 (64.7th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 65th percentile — 64.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.010 · newest: 0.011 · change: +0.001
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
- Fedoraproject Fedora — versions 39
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking)
- www.mozilla.org/security/advisories/mfsa2023-41/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2023-42/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2023-43/ (Vendor Advisory)
- www.debian.org/security/2023/dsa-5506 (Patch, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2023/09/msg00034.html (Patch, Mailing List, Third Party Advisory)
- www.debian.org/security/2023/dsa-5513 (Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (Mailing List, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2023/10/msg00015.html (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2023-5171?
- CVE-2023-5171 is a medium-severity vulnerability in Mozilla Firefox, classified under Use After Free. CVSS score: 6.5/10. Published 2023-09-27.
- How severe is CVE-2023-5171?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2023-5171 known to be exploited?
- 5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.