Description
If Firefox is installed to a user-writable directory, the Mozilla Maintenance Service would execute updater.exe from the install location with system privileges. Although the Mozilla Maintenance Service does ensure that updater.exe is signed by Mozilla, the version could have been rolled back to a previous version which would have allowed exploitation of an older bug and arbitrary code execution with System Privileges. *Note: This issue only affected Windows operating systems. Other operating systems are unaffected.*. This vulnerability affects Firefox < 80, Thunderbird < 78.2, Thunderbird < 68.12, Firefox ESR < 68.12, and Firefox ESR < 78.2.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox | unspecified – < 80 | 80 |
| Mozilla | Thunderbird | unspecified – < 78.2, unspecified – < 68.12 | 78.2 |
| Mozilla | Firefox ESR | unspecified – < 68.12, unspecified – < 78.2 | 68.12 |
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.
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP2 | MozillaFirefox | 78.3.0-8.6.1 | SUSE-SU-2020:2749-1 |
| SLES 15 SP2 | MozillaThunderbird | 68.12.0-3.94.1 | SUSE-SU-2020:2552-1 |
| SLES 15 SP1 | MozillaFirefox | 78.2.0-3.105.1 | SUSE-SU-2020:2563-1 |
| SLES 15 SP1 | MozillaThunderbird | 68.12.0-3.94.1 | SUSE-SU-2020:2552-1 |
| SLES 12 SP5 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SLES 12 SP4 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SLES 12 SP3 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
Show 13 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SLES 11 SP4 | MozillaFirefox | 78.2.0-78.90.2 | SUSE-SU-2020:14489-1 |
| SLES for SAP 12 SP5 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SLES for SAP 12 SP4 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SLES for SAP 12 SP3 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SLES for SAP 12 SP2 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SUSE OpenStack Cloud Crowbar 9 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SUSE OpenStack Cloud Crowbar 8 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SUSE OpenStack Cloud 9 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SUSE OpenStack Cloud 8 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SUSE OpenStack Cloud 7 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SUSE HPE Helion OpenStack 8 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
| SUSE Enterprise Storage 5 | MozillaFirefox | 78.2.0-112.19.2 | SUSE-SU-2020:2544-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 92.0-1.2 | openSUSE-SU-2024:10600-1 |
| openSUSE Tumbleweed | MozillaThunderbird | 91.1.1-1.1 | openSUSE-SU-2024:10601-1 |
| openSUSE Tumbleweed | firefox-esr | 128.5.1-1.1 | openSUSE-SU-2024:14572-1 |
| openSUSE Leap 15.2 | MozillaFirefox | 78.2.0-lp152.2.18.1 | openSUSE-SU-2020:1391-1 |
| openSUSE Leap 15.2 | MozillaThunderbird | 68.12.0-lp152.2.10.1 | openSUSE-SU-2020:1392-1 |
| openSUSE Leap 15.1 | MozillaFirefox | 78.2.0-lp151.2.65.1 | openSUSE-SU-2020:1384-1 |
| openSUSE Leap 15.1 | MozillaThunderbird | 68.12.0-lp151.2.50.1 | openSUSE-SU-2020:1383-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | librewolf | 80.0-r0 | — |
| Alpine v3.23 | firefox +1 | 80.0-r0 | — |
| Alpine v3.23 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.22 | firefox +1 | 80.0-r0 | — |
| Alpine v3.22 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.21 | firefox +1 | 80.0-r0 | — |
| Alpine v3.21 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.20 | firefox | 80.0-r0 | — |
| Alpine v3.20 | firefox-esr | 78.2.0-r0 | — |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | firefox | 80.0-r0 | — |
| Alpine v3.19 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.18 | firefox | 80.0-r0 | — |
| Alpine v3.18 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.17 | firefox | 80.0-r0 | — |
| Alpine v3.17 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.16 | firefox | 80.0-r0 | — |
| Alpine v3.16 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.15 | firefox | 80.0-r0 | — |
| Alpine v3.15 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.14 | firefox | 80.0-r0 | — |
| Alpine v3.14 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.13 | firefox | 80.0-r0 | — |
| Alpine v3.13 | firefox-esr | 78.2.0-r0 | — |
| Alpine v3.12 | firefox | 80.0-r0 | — |
| Alpine v3.12 | firefox-esr | 78.2.0-r0 | — |
Advisories 12
- SUSE-SU-2020:2552-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2544-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:14489-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:1384-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2563-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10600-1 MozillaFirefox-92.0-1.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2749-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:1391-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:1383-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:1392-1 Security update for MozillaThunderbird 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-2024:10601-1 MozillaThunderbird-91.1.1-1.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
References
- https://www.mozilla.org/security/advisories/mfsa2020-41/
- https://www.mozilla.org/security/advisories/mfsa2020-36/
- https://www.mozilla.org/security/advisories/mfsa2020-38/
- https://www.mozilla.org/security/advisories/mfsa2020-40/
- https://www.mozilla.org/security/advisories/mfsa2020-37/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1643199