Description
Mozilla developers Andrew McCreight, Nicolas B. Pierron, and the Mozilla Fuzzing Team reported memory safety bugs present in Firefox 100 and Firefox ESR 91.9. 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 Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Thunderbird | unspecified – < 91.10 | 91.10 |
| Mozilla | Firefox | unspecified – < 101 | 101 |
| Mozilla | Firefox ESR | unspecified – < 91.10 | 91.10 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | firefox-esr | 91.10.0esr-1 | — |
| Debian 14 | thunderbird | 1:91.10.0-1 | — |
| Debian 13 | firefox-esr | 91.10.0esr-1 | — |
| Debian 13 | thunderbird | 1:91.10.0-1 | — |
| Debian 12 | firefox-esr | 91.10.0esr-1 | — |
| Debian 12 | thunderbird | 1:91.10.0-1 | — |
| Debian 11 | firefox-esr | 91.10.0esr-1~deb11u1 | DSA-5156-1 |
| Debian 11 | thunderbird | 1:91.10.0-1~deb11u1 | DSA-5158-1 |
| Debian 10 | firefox-esr | 91.10.0esr-1~deb10u1 | DSA-5156-1 |
| Debian 10 | thunderbird | 1:91.10.0-1~deb10u1 | DSA-5158-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 9 | firefox-esr | 91.10.0esr-1~deb9u1 | DLA-3040-1 |
| Debian 9 | thunderbird | 1:91.10.0-1~deb9u1 | DLA-3041-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | mozjs78 +1 | No fix yet | — |
| Ubuntu 22.04 LTS | thunderbird | 1:91.11.0+build2-0ubuntu0.22.04.1 | USN-5512-1 |
| Ubuntu 20.04 LTS | firefox | 101.0.1+build1-0ubuntu0.20.04.1 | USN-5475-1 |
| Ubuntu 20.04 LTS | mozjs52 +1 | No fix yet | — |
| Ubuntu 20.04 LTS | thunderbird | 1:91.11.0+build2-0ubuntu0.20.04.1 | USN-5512-1 |
| Ubuntu 18.04 LTS | firefox | 101.0.1+build1-0ubuntu0.18.04.1 | USN-5475-1 |
| Ubuntu 18.04 LTS | mozjs38 +1 | No fix yet | — |
| Ubuntu 18.04 LTS | thunderbird | 1:91.11.0+build2-0ubuntu0.18.04.1 | USN-5512-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | firefox +1 | 91.10.0-1.el9_0 | RHSA-2022:4892, RHSA-2022:4873 |
| RHEL 8 | firefox +1 | 91.10.0-1.el8_6 | RHSA-2022:4887, RHSA-2022:4872 |
| RHEL 7 | firefox +1 | 91.10.0-1.el7_9 | RHSA-2022:4891, RHSA-2022:4870 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8.4 EUS | firefox +1 | 91.10.0-1.el8_4 | RHSA-2022:4889, RHSA-2022:4875 |
| RHEL 8.2 EUS | firefox +1 | 91.10.0-1.el8_2 | RHSA-2022:4890, RHSA-2022:4876 |
| RHEL 8.1 E4S | firefox +1 | 91.10.0-1.el8_1 | RHSA-2022:4888, RHSA-2022:4871 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | firefox +1 | 91.10.0-1.el8_6 | RLSA-2022:4887, RLSA-2022:4872 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP4 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| SLES 15 SP4 | MozillaThunderbird | 91.10.0-150200.8.73.1 | SUSE-SU-2022:2062-1 |
| SLES 15 SP3 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| SLES 15 SP3 | MozillaThunderbird | 91.10.0-150200.8.73.1 | SUSE-SU-2022:2062-1 |
| SLES 15 SP2 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| SLES 15 SP1 | MozillaFirefox | 91.10.0-150000.150.44.1 | SUSE-SU-2022:1927-1 |
| SLES 15 | MozillaFirefox | 91.10.0-150000.150.44.1 | SUSE-SU-2022:1927-1 |
Show 23 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP5 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SLES 12 SP4 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SLES 12 SP3 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SLES 12 SP2 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SLES for SAP 15 SP2 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| SLES for SAP 15 SP1 | MozillaFirefox | 91.10.0-150000.150.44.1 | SUSE-SU-2022:1927-1 |
| SLES for SAP 15 | MozillaFirefox | 91.10.0-150000.150.44.1 | SUSE-SU-2022:1927-1 |
| SLES for SAP 12 SP5 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SLES for SAP 12 SP4 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SLES for SAP 12 SP3 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SLE HPC 15 SP2 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| SLE HPC 15 SP1 | MozillaFirefox | 91.10.0-150000.150.44.1 | SUSE-SU-2022:1927-1 |
| SLE HPC 15 | MozillaFirefox | 91.10.0-150000.150.44.1 | SUSE-SU-2022:1927-1 |
| SUSE OpenStack Cloud Crowbar 9 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SUSE OpenStack Cloud Crowbar 8 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SUSE OpenStack Cloud 9 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SUSE OpenStack Cloud 8 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SUSE Manager Server 4.1 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| SUSE Manager Retail Branch Server 4.1 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| SUSE Manager Proxy 4.1 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| SUSE HPE Helion OpenStack 8 | MozillaFirefox | 91.10.0-112.114.1 | SUSE-SU-2022:1921-1 |
| SUSE Enterprise Storage 7 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| SUSE Enterprise Storage 6 | MozillaFirefox | 91.10.0-150000.150.44.1 | SUSE-SU-2022:1927-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 101.0-1.1 | openSUSE-SU-2024:12121-1 |
| openSUSE Tumbleweed | MozillaThunderbird | 91.10.0-1.1 | openSUSE-SU-2024:12117-1 |
| openSUSE Tumbleweed | firefox-esr | 128.5.1-1.1 | openSUSE-SU-2024:14572-1 |
| openSUSE Leap 15.4 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| openSUSE Leap 15.4 | MozillaThunderbird | 91.10.0-150200.8.73.1 | SUSE-SU-2022:2062-1 |
| openSUSE Leap 15.3 | MozillaFirefox | 91.10.0-150200.152.43.1 | SUSE-SU-2022:1920-1 |
| openSUSE Leap 15.3 | MozillaThunderbird | 91.10.0-150200.8.73.1 | SUSE-SU-2022:2062-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | librewolf | 101.0-r0 | — |
| Alpine v3.23 | firefox +1 | 101.0-r0 | — |
| Alpine v3.23 | firefox-esr +1 | 91.10.0-r0 | — |
| Alpine v3.22 | firefox +1 | 101.0-r0 | — |
| Alpine v3.22 | firefox-esr +1 | 91.10.0-r0 | — |
| Alpine v3.21 | firefox +1 | 101.0-r0 | — |
| Alpine v3.21 | firefox-esr +1 | 91.10.0-r0 | — |
| Alpine v3.20 | firefox | 101.0-r0 | — |
| Alpine v3.20 | firefox-esr +1 | 91.10.0-r0 | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | firefox | 101.0-r0 | — |
| Alpine v3.19 | firefox-esr +1 | 91.10.0-r0 | — |
| Alpine v3.18 | firefox | 101.0-r0 | — |
| Alpine v3.18 | firefox-esr +1 | 91.10.0-r0 | — |
| Alpine v3.17 | firefox | 101.0-r0 | — |
| Alpine v3.17 | firefox-esr +1 | 91.10.0-r0 | — |
| Alpine v3.16 | firefox | 101.0-r0 | — |
| Alpine v3.16 | firefox-esr +1 | 91.10.0-r0 | — |
| Alpine v3.15 | firefox-esr | 91.10.0-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | thunderbird | 91.11.0-2.amzn2.0.1 | ALAS2-2022-1828 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | firefox +1 | 91.10.0-1.0.1.el9_0 | ELSA-2022-4892, ELSA-2022-4873 |
| Oracle Linux 8 | firefox +1 | 91.10.0-1.0.1.el8_6 | ELSA-2022-4887, ELSA-2022-4872 |
| Oracle Linux 7 | firefox +1 | 91.10.0-1.0.1.el7_9 | ELSA-2022-4891, ELSA-2022-4870 |
Advisories 36
- RHSA-2022:4891 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2022:4870 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- USN-5475-1 firefox vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-5512-1 thunderbird vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-5158-1 thunderbird - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-5156-1 firefox-esr - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-3040-1 firefox-esr - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-3041-1 thunderbird - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2022:4872 Important: firefox security update Rocky Linux Security Advisories · Feb 5, 2026
- RLSA-2022:4887 Important: thunderbird security update Rocky Linux Security Advisories · Feb 5, 2026
- SUSE-SU-2022:1920-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:12117-1 MozillaThunderbird-91.10.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2022:1921-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:12121-1 MozillaFirefox-101.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2022:2062-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:14572-1 firefox-esr-128.5.1-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- RHSA-2022:4892 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2022:4889 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2022:4890 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2022:4888 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2022:4876 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2022:4887 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2022:4875 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2022:4873 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2022:4871 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2022:4872 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- WID-SEC-2022-1335 Xerox FreeFlow Print Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 6, 2025
- SUSE-SU-2022:1927-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · May 2, 2025
- WID-SEC-2022-0019 Mozilla Firefox und Thunderbird: Mehrere Schwachstellen ermöglichen Codeausführung BSI CERT-Bund (WID) · Jul 10, 2024
- ALAS2-2022-1828 Important: thunderbird security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Jul 3, 2024
- ELSA-2022-4892 Important: thunderbird security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jun 30, 2022
- ELSA-2022-4873 Important: firefox security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jun 30, 2022
- ELSA-2022-4887 Important: thunderbird security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Jun 6, 2022
- ELSA-2022-4891 Important: thunderbird security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jun 3, 2022
- ELSA-2022-4872 Important: firefox security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Jun 2, 2022
- ELSA-2022-4870 Important: firefox security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jun 2, 2022