Buffer overflow in Mozilla Firefox
CVE-2021-38493
Mozilla developers reported memory safety bugs present in Firefox 91 and Firefox ESR 78.13. 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 affects Firefox ESR < 78.14, Thunderbird < 78.14, and Firefox < 92.
Vulnerability class: Buffer Overflow
EPSS: 0.012 (65.1th percentile) — read the EPSS interpretation.
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.
Affected products
- Mozilla Firefox — versions unspecified
- Mozilla Firefox Esr — versions unspecified
- Mozilla Firefox_esr
- Mozilla Thunderbird — versions unspecified
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@mozilla.org (x_refsource_MISC, Vendor Advisory)
- security@mozilla.org (x_refsource_MISC, Vendor Advisory)
- security@mozilla.org (x_refsource_MISC, Vendor Advisory)
- security@mozilla.org (x_refsource_MISC, Vendor Advisory)
- security@mozilla.org (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)
- security@mozilla.org (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)
Frequently asked questions
- What is CVE-2021-38493?
- CVE-2021-38493 is a high-severity vulnerability in Mozilla Firefox, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2021-11-03.
- How severe is CVE-2021-38493?
- High severity. CVSS v3 base score is 8.8 out of 10.
- Is CVE-2021-38493 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.