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.
CVSS Details
- CVSS 3.1 Base Score: 8.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade firefoxUpgrade thunderbird | May 4, 2022 | Jun 24, 2021 |
| Alpine Linux | — | Upgrade librewolfUpgrade firefoxUpgrade thunderbirdUpgrade firefox-esr | Aug 22, 2024 | Jun 24, 2021 |
| Amazon Linux Ami 2 | — | Upgrade thunderbirdUpgrade thunderbird-debuginfo | May 26, 2021 | May 26, 2021 |
| Arch Linux | — | Upgrade to the latest version of Arch Linux | Jul 11, 2025 | Jun 24, 2021 |
| Centos_linux | — | Upgrade thunderbirdUpgrade firefox-debugsourceUpgrade thunderbird-debuginfoUpgrade thunderbird-debugsourceUpgrade firefoxUpgrade firefox-debuginfo | Jun 1, 2021 | Apr 26, 2021 |
| Debian | — | Upgrade thunderbirdUpgrade firefox-esr | Apr 23, 2021 | Apr 23, 2021 |
| Gentoo Linux | — | Upgrade mail-client/thunderbird.Upgrade www-client/firefox-bin.Upgrade mail-client/thunderbird-bin.Upgrade www-client/firefox. | May 3, 2021 | Apr 30, 2021 |
| Mfsa2021 15 | — | Upgrade to Mozilla Firefox ESR version 78.10 | Apr 20, 2021 | Apr 19, 2021 |
| Mfsa2021 16 | — | Upgrade to Mozilla Firefox version 88.0 | Apr 20, 2021 | Apr 19, 2021 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 78.10 | Apr 20, 2021 | Apr 19, 2021 |
| Oracle Solaris | — | Upgrade web/browser/firefox to version 78.10.0-11.4.34.0.1.94.3 on Solaris 11.4Upgrade web/data/firefox-bookmarks to version 78.10.0-11.4.34.0.1.94.3 on Solaris 11.4Upgrade mail/thunderbird to version 78.10.0-11.4.34.0.1.94.3 on Solaris 11.4 | Jun 16, 2021 | Jun 16, 2021 |
| Oracle_linux | — | Upgrade thunderbirdUpgrade firefox | Apr 27, 2021 | Apr 19, 2021 |
| Redhat_linux | — | Upgrade thunderbird-debugsourceUpgrade firefox-debugsourceUpgrade firefoxNo solution existsUpgrade firefox-debuginfoUpgrade thunderbird-debuginfoUpgrade thunderbird | Apr 27, 2021 | Apr 26, 2021 |
| Suse | — | Upgrade mozillafirefox-branding-upstreamUpgrade mozillafirefoxUpgrade mozillafirefox-translations-commonUpgrade mozillathunderbirdUpgrade mozillafirefox-buildsymbolsUpgrade mozillafirefox-translations-otherUpgrade mozillathunderbird-translations-otherUpgrade mozillathunderbird-translations-commonUpgrade mozillafirefox-devel | Apr 27, 2021 | Apr 23, 2021 |
| Ubuntu | — | Upgrade thunderbirdUpgrade firefox | Apr 27, 2021 | Apr 27, 2021 |
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