Description
Sandbox escape due to incorrect boundary conditions in the WebRTC component. This vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox | — | 153.3 |
| Mozilla | Thunderbird | — | 153.3 |
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 | thunderbird | 1:153.3.0esr-1 | — |
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 | 153.3.0-150400.157.8.1 | SUSE-SU-2026:4264-1 |
| SLES 15 SP7 | MozillaThunderbird | 153.4.0-150400.13.6.1 | SUSE-SU-2026:4627-1 |
| SLES 15 SP6 | MozillaFirefox | 153.3.0-150400.157.8.1 | SUSE-SU-2026:4264-1 |
| SLES 15 SP5 | MozillaFirefox | 153.3.0-150400.157.8.1 | SUSE-SU-2026:4264-1 |
| SLES 15 SP4 | MozillaFirefox | 153.3.0-150400.157.8.1 | SUSE-SU-2026:4264-1 |
| SLES 12 SP5 | MozillaFirefox | 153.3.0-118.8.1 | SUSE-SU-2026:4247-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | MozillaFirefox | 153.3.0-160000.1.1 | SUSE-SU-2026:23918-1 |
| SLES for SAP 15 SP6 | MozillaFirefox | 153.3.0-150400.157.8.1 | SUSE-SU-2026:4264-1 |
| SLES for SAP 15 SP5 | MozillaFirefox | 153.3.0-150400.157.8.1 | SUSE-SU-2026:4264-1 |
| SLES for SAP 15 SP4 | MozillaFirefox | 153.3.0-150400.157.8.1 | SUSE-SU-2026:4264-1 |
| SLES 16.0 | MozillaFirefox | 153.3.0-160000.1.1 | SUSE-SU-2026:23918-1 |
| SLE HPC 15 SP5 | MozillaFirefox | 153.3.0-150400.157.8.1 | SUSE-SU-2026:4264-1 |
| SLE HPC 15 SP4 | MozillaFirefox | 153.3.0-150400.157.8.1 | SUSE-SU-2026:4264-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 156.0-1.1 | openSUSE-SU-2026:11826-1 |
| openSUSE Tumbleweed | MozillaThunderbird | 153.4.0-1.1 | openSUSE-SU-2026:12098-1 |
| openSUSE Tumbleweed | firefox-esr | 153.3.0-1.1 | openSUSE-SU-2026:11796-1 |
| openSUSE Leap 16.0 | MozillaFirefox | 153.3.0-160000.1.1 | openSUSE-SU-2026:21951-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | firefox | 140.17.0-1.amzn2023.0.1 | ALAS2023-2026-3214 |
Advisories 10
- WID-SEC-2026-3375 Mozilla Firefox und Thunderbird: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 8, 2026
- ALAS2023-2026-3214 Important: firefox security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 29, 2026
- SUSE-SU-2026:4627-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Oct 13, 2026
- openSUSE-SU-2026:12098-1 MozillaThunderbird-153.4.0-1.1 on GA media SUSE / openSUSE Security Updates · Oct 11, 2026
- SUSE-SU-2026:23918-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Sep 30, 2026
- openSUSE-SU-2026:21951-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Sep 25, 2026
- openSUSE-SU-2026:11826-1 MozillaFirefox-156.0-1.1 on GA media SUSE / openSUSE Security Updates · Sep 22, 2026
- SUSE-SU-2026:4264-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Sep 19, 2026
- SUSE-SU-2026:4247-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Sep 18, 2026
- openSUSE-SU-2026:11796-1 firefox-esr-153.3.0-1.1 on GA media SUSE / openSUSE Security Updates · Sep 17, 2026