Vulnerability in Mozilla Firefox
CVE-2021-23954
Using the new logical assignment operators in a JavaScript switch statement could have caused a type confusion, leading to a memory corruption and a potentially exploitable crash. This vulnerability affects Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7.
EPSS: 0.011 (62.3th 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 < 85
- Mozilla Firefox Esr — versions < 78.7
- Mozilla Firefox_esr
- Mozilla Thunderbird — versions < 78.7
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 (Permissions Required, x_refsource_MISC, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-23954?
- CVE-2021-23954 is a high-severity vulnerability in Mozilla Firefox, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 8.8/10. Published 2021-02-26.
- How severe is CVE-2021-23954?
- High severity. CVSS v3 base score is 8.8 out of 10.