vulnerability
MFSA2021-33 Firefox: Security Vulnerabilities fixed in Firefox 91 (CVE-2021-29986)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Aug 10, 2021 | Aug 12, 2021 | Mar 27, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Aug 10, 2021
Added
Aug 12, 2021
Modified
Mar 27, 2026
Description
A suspected race condition when calling getaddrinfo led to memory corruption and a potentially exploitable crash. *Note: This issue only affected Linux operating systems. Other operating systems are unaffected.* This vulnerability affects Thunderbird < 78.13, Thunderbird < 91, Firefox ESR < 78.13, and Firefox < 91.
Solution
mozilla-firefox-upgrade-91_0
Rapid7 Labs
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