vulnerability
Ubuntu: (Multiple Advisories) (CVE-2021-29946): Firefox vulnerabilities
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Apr 27, 2021 | Apr 27, 2021 | Mar 27, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Apr 27, 2021
Added
Apr 27, 2021
Modified
Mar 27, 2026
Description
Ports that were written as an integer overflow above the bounds of a 16-bit integer could have bypassed port blocking restrictions when used in the Alt-Svc header. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.
Solutions
ubuntu-upgrade-firefoxubuntu-upgrade-thunderbird
References
Rapid7 Labs
2026 Global Threat Landscape Report
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