Buffer overflow in Mozilla Firefox
CVE-2021-23978
Mozilla developers reported memory safety bugs present in Firefox 85 and Firefox ESR 78.7. 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 < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.
Vulnerability class: Buffer Overflow
EPSS: 0.015 (72.1th 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 < 86
- Mozilla Firefox Esr — versions < 78.8
- Mozilla Firefox_esr
- Mozilla Thunderbird — versions < 78.8
- Debian Debian_linux — versions 9.0, 10.0
Weakness classification (CWE)
References
- security@mozilla.org (x_refsource_MISC, Release Notes, Vendor Advisory)
- security@mozilla.org (x_refsource_MISC, Release Notes, Vendor Advisory)
- security@mozilla.org (x_refsource_MISC, Release Notes, Vendor Advisory)
- security@mozilla.org (x_refsource_MISC, Issue Tracking, Broken Link, Vendor Advisory)
- security@mozilla.org (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
- security@mozilla.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
- 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-2021-23978?
- CVE-2021-23978 is a high-severity vulnerability in Mozilla Firefox, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2021-02-26.
- How severe is CVE-2021-23978?
- High severity. CVSS v3 base score is 8.8 out of 10.