Description
Memory safety bugs present in Firefox 119, Firefox ESR 115.4, and Thunderbird 115.4. 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 Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox | unspecified – < 120 | 120 |
| Mozilla | Firefox ESR | unspecified – < 115.5.0 | 115.5.0 |
| Mozilla | Thunderbird | unspecified – < 115.5 | 115.5 |
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 | 115.5.0esr-1 | — |
| Debian 14 | thunderbird | 1:115.5.0-1 | — |
| Debian 13 | firefox-esr | 115.5.0esr-1 | — |
| Debian 13 | thunderbird | 1:115.5.0-1 | — |
| Debian 12 | firefox-esr | 115.5.0esr-1~deb12u1 | DSA-5561-1 |
| Debian 12 | thunderbird | 1:115.5.0-1~deb12u1 | DSA-5566-1 |
| Debian 11 | firefox-esr | 115.5.0esr-1~deb11u1 | DSA-5561-1 |
| Debian 11 | thunderbird | 1:115.5.0-1~deb11u1 | DSA-5566-1 |
| Debian 10 | firefox-esr | 115.5.0esr-1~deb10u1 | DLA-3661-1 |
| Debian 10 | thunderbird | 1:115.5.0-1~deb10u1 | DLA-3674-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | mozjs102 | No fix yet | — |
| Ubuntu 24.04 LTS | thunderbird | 1:115.5.0+build1-0ubuntu1 | — |
| Ubuntu 22.04 LTS | mozjs78 +2 | No fix yet | — |
| Ubuntu 22.04 LTS | thunderbird | 1:115.5.0+build1-0ubuntu0.22.04.1 | USN-6515-1 |
| Ubuntu 20.04 LTS | firefox | 120.0+build2-0ubuntu0.20.04.1 | USN-6509-1 |
| Ubuntu 20.04 LTS | mozjs52 +1 | No fix yet | — |
| Ubuntu 20.04 LTS | thunderbird | 1:115.5.0+build1-0ubuntu0.20.04.1 | USN-6515-1 |
| Ubuntu 18.04 LTS | mozjs38 +1 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | firefox +2 | 115.5.0-1.el9_3 | RHSA-2023:7507, RHSA-2023:7501 |
| RHEL 8 | firefox +1 | 115.5.0-1.el8_9 | RHSA-2023:7508, RHSA-2023:7500 |
| RHEL 7 | firefox +1 | 115.5.0-1.el7_9 | RHSA-2023:7509, RHSA-2023:7505 |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.2 EUS | firefox +2 | 115.5.0-1.el9_2 | RHSA-2023:7577, RHSA-2023:7499 |
| RHEL 9.0 EUS | firefox +1 | 115.5.0-1.el9_0 | RHSA-2023:7510, RHSA-2023:7506 |
| RHEL 8.8 EUS | firefox +1 | 115.5.0-1.el8_8 | RHSA-2023:7511, RHSA-2023:7504 |
| RHEL 8.6 EUS | firefox +1 | 115.5.0-1.el8_6 | RHSA-2023:7512, RHSA-2023:7503 |
| RHEL 8.4 TUS | firefox +1 | 115.5.0-1.el8_4 | RHSA-2023:7570, RHSA-2023:7569 |
| RHEL 8.4 E4S | firefox +1 | 115.5.0-1.el8_4 | RHSA-2023:7570, RHSA-2023:7569 |
| RHEL 8.4 AUS | firefox +1 | 115.5.0-1.el8_4 | RHSA-2023:7570, RHSA-2023:7569 |
| RHEL 8.2 TUS | firefox +1 | 115.5.0-1.el8_2 | RHSA-2023:7574, RHSA-2023:7573 |
| RHEL 8.2 E4S | firefox +1 | 115.5.0-1.el8_2 | RHSA-2023:7574, RHSA-2023:7573 |
| RHEL 8.2 AUS | firefox +1 | 115.5.0-1.el8_2 | RHSA-2023:7574, RHSA-2023:7573 |
| RHEL 8.1 E4S | firefox +1 | 115.5.0-1.el8_1 | RHSA-2023:7547, RHSA-2023:7502 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 9 | firefox +1 | 115.5.0-1.el9_3.alma.1 | ALSA-2023:7507 |
| AlmaLinux 9 | thunderbird | 115.5.0-1.el9_3.alma | ALSA-2023:7501 |
| AlmaLinux 8 | firefox +1 | 115.5.0-1.el8_9.alma.1 | ALSA-2023:7508, ALSA-2023:7500 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | thunderbird | 115.5.0-1.el8_9 | RLSA-2023:7500 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLES 15 SP5 | MozillaThunderbird | 115.5.0-150200.8.139.1 | SUSE-SU-2023:4588-1 |
| SLES 15 SP4 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLES 15 SP4 | MozillaThunderbird | 115.5.0-150200.8.139.1 | SUSE-SU-2023:4588-1 |
| SLES 15 SP3 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLES 15 SP2 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLES 15 SP1 | MozillaFirefox | 115.6.0-150000.150.119.1 | SUSE-SU-2023:4929-1 |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP5 | MozillaFirefox | 115.6.0-112.194.1 | SUSE-SU-2023:4912-1 |
| SLES for SAP 15 SP4 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLES for SAP 15 SP3 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLES for SAP 15 SP2 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLES for SAP 15 SP1 | MozillaFirefox | 115.6.0-150000.150.119.1 | SUSE-SU-2023:4929-1 |
| SLES for SAP 12 SP5 | MozillaFirefox | 115.6.0-112.194.1 | SUSE-SU-2023:4912-1 |
| SLE Real Time 15 SP4 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLE HPC 15 SP4 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLE HPC 15 SP3 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLE HPC 15 SP2 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| SLE HPC 15 SP1 | MozillaFirefox | 115.6.0-150000.150.119.1 | SUSE-SU-2023:4929-1 |
| SUSE Enterprise Storage 7.1 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 120.0-1.1 | openSUSE-SU-2024:13468-1 |
| openSUSE Tumbleweed | MozillaThunderbird | 115.5.0-1.1 | openSUSE-SU-2024:13459-1 |
| openSUSE Tumbleweed | firefox-esr | 128.5.1-1.1 | openSUSE-SU-2024:14572-1 |
| openSUSE Leap 15.5 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| openSUSE Leap 15.5 | MozillaThunderbird | 115.5.0-150200.8.139.1 | SUSE-SU-2023:4588-1 |
| openSUSE Leap 15.4 | MozillaFirefox | 115.6.0-150200.152.120.1 | SUSE-SU-2023:4928-1 |
| openSUSE Leap 15.4 | MozillaThunderbird | 115.5.0-150200.8.139.1 | SUSE-SU-2023:4588-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.23 | firefox-esr +1 | 115.5.0-r0 | — |
| Alpine v3.22 | firefox-esr +1 | 115.5.0-r0 | — |
| Alpine v3.21 | firefox-esr +1 | 115.5.0-r0 | — |
| Alpine v3.20 | firefox-esr +1 | 115.5.0-r0 | — |
| Alpine v3.19 | firefox-esr +1 | 115.5.0-r0 | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.18 | firefox-esr +1 | 115.5.0-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | thunderbird | 115.5.0-1.amzn2.0.1 | ALAS2-2024-2379 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | firefox +2 | 115.5.0-1.0.1.el9_3 | ELSA-2023-7507, ELSA-2023-7501 |
| Oracle Linux 8 | firefox +1 | 115.5.0-1.0.1.el8_9 | ELSA-2023-7508, ELSA-2023-7500 |
| Oracle Linux 7 | firefox +1 | 115.5.0-1.0.1.el7_9 | ELSA-2023-7509, ELSA-2023-7505 |
Advisories 46
- ALSA-2023:7501 Important: thunderbird security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2023:7507 Important: firefox security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2023:7500 Important: thunderbird security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2023:7508 Important: firefox security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2023:7509 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2023:7505 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- USN-6515-1 thunderbird vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-6509-1 firefox vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- RHSA-2023:7573 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7574 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7577 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7569 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7570 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7547 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7508 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7510 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7506 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7499 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7507 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7503 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7511 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7504 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7512 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7500 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7502 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2023:7501 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- DSA-5566-1 thunderbird - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-5561-1 firefox-esr - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-3674-1 thunderbird - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-3661-1 firefox-esr - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2023:7500 Important: thunderbird security update Rocky Linux Security Advisories · Feb 4, 2026
- SUSE-SU-2023:4912-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:4928-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:13459-1 MozillaThunderbird-115.5.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:4588-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:4929-1 Security update for MozillaFirefox 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
- openSUSE-SU-2024:13468-1 MozillaFirefox-120.0-1.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- WID-SEC-2023-2995 Mozilla Firefox, Mozilla Firefox ESR und Mozilla Thunderbird: Mehrere Schwachstellen BSI CERT-Bund (WID) · Dec 15, 2024
- ALAS2-2024-2379 Important: thunderbird security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Jan 9, 2024
- ELSA-2023-7507 Important: firefox security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Nov 28, 2023
- ELSA-2023-7501 Important: thunderbird security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Nov 28, 2023
- ELSA-2023-7508 Important: firefox security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Nov 28, 2023
- ELSA-2023-7500 Important: thunderbird security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Nov 28, 2023
- ELSA-2023-7505 Important: thunderbird security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Nov 28, 2023
- ELSA-2023-7509 Important: firefox security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Nov 27, 2023
References
- Memory safety bugs fixed in Firefox 120, Firefox ESR 115.5, and Thunderbird 115.5
- https://www.mozilla.org/security/advisories/mfsa2023-49/
- https://www.mozilla.org/security/advisories/mfsa2023-50/
- https://www.mozilla.org/security/advisories/mfsa2023-52/
- https://www.debian.org/security/2023/dsa-5561
- https://lists.debian.org/debian-lts-announce/2023/11/msg00017.html
- https://lists.debian.org/debian-lts-announce/2023/11/msg00030.html