Description
Microsoft introduced a new feature in Windows 10 known as Cloud Clipboard which, if enabled, will record data copied to the clipboard to the cloud, and make it available on other computers in certain scenarios. Applications that wish to prevent copied data from being recorded in Cloud History must use specific clipboard formats; and Firefox before versions 94 and ESR 91.3 did not implement them. This could have caused sensitive data to be recorded to a user's Microsoft account. *This bug only affects Firefox for Windows 10+ with Cloud Clipboard enabled. Other operating systems are unaffected.*. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox | unspecified – < 94 | 94 |
| Mozilla | Thunderbird | unspecified – < 91.3 | 91.3 |
| Mozilla | Firefox ESR | unspecified – < 91.3 | 91.3 |
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.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | mozjs78 | 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 SP3 | MozillaFirefox | 91.3.0-152.6.1 | SUSE-SU-2021:3745-1 |
| SLES 15 SP3 | MozillaThunderbird | 91.4.0-8.45.2 | SUSE-SU-2021:4150-1 |
| SLES 15 SP2 | MozillaFirefox | 91.3.0-152.6.1 | SUSE-SU-2021:3745-1 |
| SLES 15 SP2 | MozillaThunderbird | 91.4.0-8.45.2 | SUSE-SU-2021:4150-1 |
| SLES 15 SP1 | MozillaFirefox | 91.3.0-150.6.1 | SUSE-SU-2021:3651-1 |
| SLES 15 | MozillaFirefox | 91.3.0-150.6.1 | SUSE-SU-2021:3651-1 |
| SLES 12 SP5 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
Show 16 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP4 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SLES 12 SP3 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SLES 12 SP2 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SLES for SAP 15 SP1 | MozillaFirefox | 91.3.0-150.6.1 | SUSE-SU-2021:3651-1 |
| SLES for SAP 15 | MozillaFirefox | 91.3.0-150.6.1 | SUSE-SU-2021:3651-1 |
| SLES for SAP 12 SP5 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SLES for SAP 12 SP4 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SLES for SAP 12 SP3 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SLE HPC 15 SP1 | MozillaFirefox | 91.3.0-150.6.1 | SUSE-SU-2021:3651-1 |
| SLE HPC 15 | MozillaFirefox | 91.3.0-150.6.1 | SUSE-SU-2021:3651-1 |
| SUSE OpenStack Cloud Crowbar 9 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SUSE OpenStack Cloud Crowbar 8 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SUSE OpenStack Cloud 9 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SUSE OpenStack Cloud 8 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SUSE HPE Helion OpenStack 8 | MozillaFirefox | 91.3.0-112.80.2 | SUSE-SU-2021:3721-1 |
| SUSE Enterprise Storage 6 | MozillaFirefox | 91.3.0-150.6.1 | SUSE-SU-2021:3651-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 94.0.1-1.1 | openSUSE-SU-2024:11614-1 |
| openSUSE Tumbleweed | MozillaThunderbird | 91.3.0-1.1 | openSUSE-SU-2024:11607-1 |
| openSUSE Tumbleweed | firefox-esr | 128.5.1-1.1 | openSUSE-SU-2024:14572-1 |
| openSUSE Leap 15.3 | MozillaFirefox | 91.3.0-152.6.1 | openSUSE-SU-2021:3745-1 |
| openSUSE Leap 15.3 | MozillaThunderbird | 91.4.0-8.45.2 | openSUSE-SU-2021:4150-1 |
| openSUSE Leap 15.2 | MozillaThunderbird | 91.4.0-lp152.2.52.1 | openSUSE-SU-2021:1635-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | librewolf | 94.0-r0 | — |
| Alpine v3.23 | firefox +1 | 94.0-r0 | — |
| Alpine v3.23 | firefox-esr | 91.3.0-r0 | — |
| Alpine v3.23 | thunderbird | 91.3.2-r0 | — |
| Alpine v3.22 | firefox +1 | 94.0-r0 | — |
| Alpine v3.22 | firefox-esr | 91.3.0-r0 | — |
| Alpine v3.22 | thunderbird | 91.3.2-r0 | — |
| Alpine v3.21 | firefox +1 | 94.0-r0 | — |
| Alpine v3.21 | firefox-esr | 91.3.0-r0 | — |
| Alpine v3.21 | thunderbird | 91.3.2-r0 | — |
| Alpine v3.20 | firefox | 94.0-r0 | — |
| Alpine v3.20 | firefox-esr | 91.3.0-r0 | — |
| Alpine v3.20 | thunderbird | 91.3.2-r0 | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | firefox | 94.0-r0 | — |
| Alpine v3.19 | firefox-esr | 91.3.0-r0 | — |
| Alpine v3.19 | thunderbird | 91.3.2-r0 | — |
| Alpine v3.18 | firefox | 94.0-r0 | — |
| Alpine v3.18 | firefox-esr | 91.3.0-r0 | — |
| Alpine v3.18 | thunderbird | 91.3.2-r0 | — |
| Alpine v3.17 | firefox | 94.0-r0 | — |
| Alpine v3.17 | firefox-esr | 91.3.0-r0 | — |
| Alpine v3.17 | thunderbird | 91.3.2-r0 | — |
| Alpine v3.16 | firefox | 94.0-r0 | — |
| Alpine v3.16 | firefox-esr | 91.3.0-r0 | — |
| Alpine v3.16 | thunderbird | 91.3.2-r0 | — |
| Alpine v3.15 | firefox | 94.0-r0 | — |
| Alpine v3.15 | firefox-esr | 91.3.0-r0 | — |
Advisories 11
- SUSE-SU-2021:4150-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:3651-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:4150-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11607-1 MozillaThunderbird-91.3.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:1635-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:3721-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:3745-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:3745-1 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
- WID-SEC-2023-0839 Xerox FreeFlow Print Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 6, 2025
- openSUSE-SU-2024:11614-1 MozillaFirefox-94.0.1-1.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025