CVE-2021-23960
Firefox ESR and 2 others: Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and…
CVE-2021-23960 is fixed in 11 products on 2 platforms, first by firefox 85.0+build1-0ubuntu0.18.04.1, released January 25, 2021. It is not reported as exploited. Patch Radar priority: High.
HighFixed on 2 platforms
CVSS
8.8
Important
Exploitation
None reported
No vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0129
70th percentile
Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and a potentially exploitable crash. This vulnerability affects Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7.
Where it's fixed
| Product | Fixed in | Fix | Released |
|---|---|---|---|
| Windows apps | |||
| Mozilla Firefox ESR (en-US) | 91.0 | Mozilla Firefox ESR (en-US) 91.0 | Aug 4, 2021 |
| Mozilla Thunderbird (en-US) | 78.10.0 | Mozilla Thunderbird (en-US) 78.10.0 | Apr 15, 2021 |
| Linux | |||
| firefox · RHEL 8 | 0:78.7.0-2.el8_3 | RHSA-2021:0288 | Jan 27, 2021 |
| firefox · Ubuntu 18.04.6 LTS (bionic) | 85.0+build1-0ubuntu0.18.04.1 | firefox 85.0+build1-0ubuntu0.18.04.1 | Jan 25, 2021 |
| firefox · Ubuntu 20.04 LTS (focal) | 85.0+build1-0ubuntu0.20.04.1 | firefox 85.0+build1-0ubuntu0.20.04.1 | Jan 25, 2021 |
| firefox · ol 8 | 0:78.7.0-2.0.1.el8_3 | ELSA-2021-0288 | Jan 28, 2021 |
| firefox-geckodriver · Ubuntu 18.04.6 LTS (bionic) | 85.0+build1-0ubuntu0.18.04.1 | firefox-geckodriver 85.0+build1-0ubuntu0.18.04.1 | Jan 25, 2021 |
| firefox-geckodriver · Ubuntu 20.04 LTS (focal) | 85.0+build1-0ubuntu0.20.04.1 | firefox-geckodriver 85.0+build1-0ubuntu0.20.04.1 | Jan 25, 2021 |
| firefox-mozsymbols · Ubuntu 18.04.6 LTS (bionic) | 85.0+build1-0ubuntu0.18.04.1 | firefox-mozsymbols 85.0+build1-0ubuntu0.18.04.1 | Jan 25, 2021 |
| firefox-mozsymbols · Ubuntu 20.04 LTS (focal) | 85.0+build1-0ubuntu0.20.04.1 | firefox-mozsymbols 85.0+build1-0ubuntu0.20.04.1 | Jan 25, 2021 |
| thunderbird · RHEL 8 | 0:78.7.0-1.el8_3 | RHSA-2021:0298 | Jan 28, 2021 |
| thunderbird · Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | thunderbird 1:78.8.1+build1-0ubuntu0.18.04.1 | Apr 22, 2021 |
| thunderbird · Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | thunderbird 1:78.7.1+build1-0ubuntu0.20.04.1 | Jan 25, 2021 |
| thunderbird · ol 8 | 0:78.7.0-1.0.1.el8_3 | ELSA-2021-0298 | Jan 29, 2021 |
| thunderbird-gnome-support · Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | thunderbird-gnome-support 1:78.8.1+build1-0ubuntu0.18.04.1 | Apr 22, 2021 |
| thunderbird-gnome-support · Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | thunderbird-gnome-support 1:78.7.1+build1-0ubuntu0.20.04.1 | Jan 25, 2021 |
| thunderbird-mozsymbols · Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | thunderbird-mozsymbols 1:78.8.1+build1-0ubuntu0.18.04.1 | Apr 22, 2021 |
| thunderbird-mozsymbols · Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | thunderbird-mozsymbols 1:78.7.1+build1-0ubuntu0.20.04.1 | Jan 25, 2021 |
| xul-ext-calendar-timezones · Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | xul-ext-calendar-timezones 1:78.8.1+build1-0ubuntu0.18.04.1 | Apr 22, 2021 |
| xul-ext-calendar-timezones · Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | xul-ext-calendar-timezones 1:78.7.1+build1-0ubuntu0.20.04.1 | Jan 25, 2021 |
| xul-ext-gdata-provider · Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | xul-ext-gdata-provider 1:78.8.1+build1-0ubuntu0.18.04.1 | Apr 22, 2021 |
| xul-ext-gdata-provider · Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | xul-ext-gdata-provider 1:78.7.1+build1-0ubuntu0.20.04.1 | Jan 25, 2021 |
| xul-ext-lightning · Ubuntu 18.04.6 LTS (bionic) | 1:78.8.1+build1-0ubuntu0.18.04.1 | xul-ext-lightning 1:78.8.1+build1-0ubuntu0.18.04.1 | Apr 22, 2021 |
| xul-ext-lightning · Ubuntu 20.04 LTS (focal) | 1:78.7.1+build1-0ubuntu0.20.04.1 | xul-ext-lightning 1:78.7.1+build1-0ubuntu0.20.04.1 | Jan 25, 2021 |
Patch Radar data is free to use with attribution. Terms and how to credit it.
Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.