Description
Internally found bugs present in Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154 and Thunderbird 154.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox | — | 154 |
| Mozilla | Thunderbird | — | 154 |
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.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | mozjs102 +1 | No fix yet | — |
| Ubuntu 22.04 LTS | mozjs78 +3 | No fix yet | — |
| Ubuntu 20.04 LTS | mozjs52 +1 | No fix yet | — |
| Ubuntu 18.04 LTS | mozjs38 +1 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | MozillaFirefox | 140.14.0-150200.152.251.1 | SUSE-SU-2026:3658-1 |
| SLES 15 SP6 | MozillaFirefox | 140.14.0-150200.152.251.1 | SUSE-SU-2026:3658-1 |
| SLES 15 SP5 | MozillaFirefox | 140.14.0-150200.152.251.1 | SUSE-SU-2026:3658-1 |
| SLES 15 SP4 | MozillaFirefox | 140.14.0-150200.152.251.1 | SUSE-SU-2026:3658-1 |
| SLES 12 SP5 | MozillaFirefox | 140.14.0-112.327.1 | SUSE-SU-2026:3683-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP6 | MozillaFirefox | 140.14.0-150200.152.251.1 | SUSE-SU-2026:3658-1 |
| SLES for SAP 15 SP5 | MozillaFirefox | 140.14.0-150200.152.251.1 | SUSE-SU-2026:3658-1 |
| SLES for SAP 15 SP4 | MozillaFirefox | 140.14.0-150200.152.251.1 | SUSE-SU-2026:3658-1 |
| SLE HPC 15 SP5 | MozillaFirefox | 140.14.0-150200.152.251.1 | SUSE-SU-2026:3658-1 |
| SLE HPC 15 SP4 | MozillaFirefox | 140.14.0-150200.152.251.1 | SUSE-SU-2026:3658-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 154.0-1.1 | openSUSE-SU-2026:11580-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | firefox +1 | 154.0-r0 | — |
Advisories 4
- WID-SEC-2026-2911 Mozilla Firefox, Firefox ESR und Thunderbird: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 8, 2026
- SUSE-SU-2026:3683-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Aug 26, 2026
- openSUSE-SU-2026:11580-1 MozillaFirefox-154.0-1.1 on GA media SUSE / openSUSE Security Updates · Aug 24, 2026
- SUSE-SU-2026:3658-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Aug 21, 2026