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
EPSS: 0.010 (59.9th percentile) — read the EPSS interpretation.
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.
Affected products
- Mozilla Firefox — versions unspecified
- Mozilla Firefox Esr — versions unspecified
- Mozilla Firefox_esr
- Mozilla Thunderbird — versions unspecified
- Debian Debian_linux — versions 10.0, 11.0, 12.0
- Fedoraproject Fedora — versions 39
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@mozilla.org (Permissions Required, Issue Tracking)
- security@mozilla.org (Vendor Advisory)
- security@mozilla.org (Vendor Advisory)
- security@mozilla.org (Vendor Advisory)
- security@mozilla.org (Patch, Third Party Advisory)
- security@mozilla.org (Patch, Mailing List, Third Party Advisory)
- security@mozilla.org (Third Party Advisory)
- security@mozilla.org (Mailing List, Third Party Advisory)
- security@mozilla.org (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.