Description
Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox | — | 140.11 |
| Mozilla | Thunderbird | — | 140.11 |
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 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | thunderbird | 140.11.0-1.el10_2 | RHSA-2026:22325 |
| RHEL 9 | thunderbird | 140.11.0-1.el9_8 | RHSA-2026:21381 |
| RHEL 8 | thunderbird | 140.11.0-1.el8_10 | RHSA-2026:22643 |
Show 10 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10.0 EUS | thunderbird | 140.11.0-1.el10_0 | RHSA-2026:26539 |
| RHEL 9.6 EUS | thunderbird | 140.11.0-1.el9_6 | RHSA-2026:26521 |
| RHEL 9.4 E4S | thunderbird | 140.11.0-1.el9_4 | RHSA-2026:26174 |
| RHEL 9.2 E4S | thunderbird | 140.11.0-1.el9_2 | RHSA-2026:26269 |
| RHEL 8.8 TUS | thunderbird | 140.11.0-1.el8_8 | RHSA-2026:26268 |
| RHEL 8.8 E4S | thunderbird | 140.11.0-1.el8_8 | RHSA-2026:26268 |
| RHEL 8.6 EUS Long Life | thunderbird | 140.11.0-1.el8_6 | RHSA-2026:26536 |
| RHEL 8.6 AUS | thunderbird | 140.11.0-1.el8_6 | RHSA-2026:26536 |
| RHEL 8.4 EUS Long Life | thunderbird | 140.11.0-1.el8_4 | RHSA-2026:26270 |
| RHEL 8.4 AUS | thunderbird | 140.11.0-1.el8_4 | RHSA-2026:26270 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | thunderbird | 140.11.0-1.el10_2.alma.1 | ALSA-2026:22325 |
| AlmaLinux 9 | thunderbird | 140.11.0-1.el9_8.alma.1 | ALSA-2026:21381 |
| AlmaLinux 8 | thunderbird | 140.11.0-1.el8_10.alma.1 | ALSA-2026:22643 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | thunderbird | 140.11.0-1.el10_2 | RLSA-2026:22325 |
| Rocky Linux 9 | thunderbird | 140.11.0-1.el9_8 | RLSA-2026:21381 |
| Rocky Linux 8 | thunderbird | 140.11.0-1.el8_10 | RLSA-2026:22643 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 151.0.1-1.1 | openSUSE-SU-2026:10863-1 |
| openSUSE Tumbleweed | MozillaThunderbird | 140.11.1-1.1 | openSUSE-SU-2026:10864-1 |
| openSUSE Tumbleweed | firefox-esr | 140.11.0-1.1 | openSUSE-SU-2026:10813-1 |
| openSUSE Leap 16.0 | MozillaThunderbird | 140.12.0-bp160.1.1 | openSUSE-SU-2026:21168-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | thunderbird | 140.12.0-1.0.1.el10_2 | ELSA-2026-22325 |
| Oracle Linux 9 | thunderbird | 140.11.0-1.0.1.el9_8 | ELSA-2026-21381 |
| Oracle Linux 8 | thunderbird | 140.11.0-1.0.1.el8_10 | ELSA-2026-22643 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | firefox | 140.11-r0 | — |
Advisories 25
- ALSA-2026:21381 Important: thunderbird security update AlmaLinux Security Advisories · Nov 6, 2026
- ALSA-2026:22325 Important: thunderbird security update AlmaLinux Security Advisories · Nov 6, 2026
- ALSA-2026:22643 Important: thunderbird security update AlmaLinux Security Advisories · Nov 6, 2026
- WID-SEC-2026-2455 Oracle Solaris Drittanbieterkomponenten: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 27, 2026
- RHSA-2026:26536 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- RHSA-2026:26539 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- RHSA-2026:26521 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- RHSA-2026:26270 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- RHSA-2026:26268 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- RHSA-2026:26269 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- RHSA-2026:26174 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- RHSA-2026:22643 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- RHSA-2026:22325 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- RHSA-2026:21381 Red Hat Security Advisory: thunderbird security update Red Hat Security Advisories (RHSA) · Jul 29, 2026
- WID-SEC-2026-1606 Mozilla Firefox und Thunderbird: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jul 20, 2026
- ELSA-2026-22325 Important: thunderbird security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Jul 17, 2026
- openSUSE-SU-2026:21168-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Jun 30, 2026
- ELSA-2026-21381 Important: thunderbird security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jun 23, 2026
- RLSA-2026:22643 Important: thunderbird security update Rocky Linux Security Advisories · Jun 6, 2026
- RLSA-2026:22325 Important: thunderbird security update Rocky Linux Security Advisories · Jun 5, 2026
- ELSA-2026-22643 Important: thunderbird security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Jun 3, 2026
- RLSA-2026:21381 Important: thunderbird security update Rocky Linux Security Advisories · May 30, 2026
- openSUSE-SU-2026:10863-1 MozillaFirefox-151.0.1-1.1 on GA media SUSE / openSUSE Security Updates · May 28, 2026
- openSUSE-SU-2026:10864-1 MozillaThunderbird-140.11.1-1.1 on GA media SUSE / openSUSE Security Updates · May 28, 2026
- openSUSE-SU-2026:10813-1 firefox-esr-140.11.0-1.1 on GA media SUSE / openSUSE Security Updates · May 20, 2026