CVE-2021-38506
Mozilla Firefox ESR and 3 others: Through a series of navigations, Firefox could have entered fullscreen mode without notification or warning…
CVE-2021-38506 is fixed in 12 products on 2 platforms, first by Mozilla Thunderbird (en-US) 91.3.0, released November 1, 2021. It is not reported as exploited. Patch Radar priority: High.
HighFixed on 2 platforms
CVSS
7.5
Important
Exploitation
None reported
No vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0151
74th percentile
Through a series of navigations, Firefox could have entered fullscreen mode without notification or warning to the user. This could lead to spoofing attacks on the browser UI including phishing. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.
Where it's fixed
| Product | Fixed in | Fix | Released |
|---|---|---|---|
| Windows apps | |||
| Mozilla Firefox ESR (en-US) | 102.0 | Mozilla Firefox ESR (en-US) 102.0 | Jun 23, 2022 |
| Mozilla Thunderbird (en-US) | 91.3.0 | Mozilla Thunderbird (en-US) 91.3.0 | Nov 1, 2021 |
| Linux | |||
| firefox · RHEL 8 | 0:91.3.0-1.el8_4 | RHSA-2021:4123 | Nov 3, 2021 |
| firefox · Ubuntu 18.04.6 LTS (bionic) | 94.0+build3-0ubuntu0.18.04.1 | firefox 94.0+build3-0ubuntu0.18.04.1 | Nov 2, 2021 |
| firefox · Ubuntu 20.04 LTS (focal) | 94.0+build3-0ubuntu0.20.04.1 | firefox 94.0+build3-0ubuntu0.20.04.1 | Nov 2, 2021 |
| firefox · Ubuntu 22.04.1 LTS (jammy) | 94.0+build3-0ubuntu1 | firefox 94.0+build3-0ubuntu1 | Nov 2, 2021 |
| firefox · ol 8 | 0:91.3.0-1.0.1.el8_4 | ELSA-2021-4123 | Nov 4, 2021 |
| firefox-esr · Debian 12.15 (bookworm) | 91.3.0esr-1 | DEBIAN-CVE-2021-38506 | Dec 8, 2021 |
| firefox-esr · Debian 13.5 (trixie) | 91.3.0esr-1 | DEBIAN-CVE-2021-38506 | Dec 8, 2021 |
| firefox-esr · Debian 14 | 91.3.0esr-1 | DEBIAN-CVE-2021-38506 | Dec 8, 2021 |
| firefox-geckodriver · Ubuntu 18.04.6 LTS (bionic) | 94.0+build3-0ubuntu0.18.04.1 | firefox-geckodriver 94.0+build3-0ubuntu0.18.04.1 | Nov 2, 2021 |
| firefox-geckodriver · Ubuntu 20.04 LTS (focal) | 94.0+build3-0ubuntu0.20.04.1 | firefox-geckodriver 94.0+build3-0ubuntu0.20.04.1 | Nov 2, 2021 |
| firefox-geckodriver · Ubuntu 22.04.1 LTS (jammy) | 94.0+build3-0ubuntu1 | firefox-geckodriver 94.0+build3-0ubuntu1 | Nov 2, 2021 |
| firefox-mozsymbols · Ubuntu 18.04.6 LTS (bionic) | 94.0+build3-0ubuntu0.18.04.1 | firefox-mozsymbols 94.0+build3-0ubuntu0.18.04.1 | Nov 2, 2021 |
| firefox-mozsymbols · Ubuntu 20.04 LTS (focal) | 94.0+build3-0ubuntu0.20.04.1 | firefox-mozsymbols 94.0+build3-0ubuntu0.20.04.1 | Nov 2, 2021 |
| firefox-mozsymbols · Ubuntu 22.04.1 LTS (jammy) | 94.0+build3-0ubuntu1 | firefox-mozsymbols 94.0+build3-0ubuntu1 | Nov 2, 2021 |
| thunderbird · Debian 12.15 (bookworm) | 1:91.3.0-1 | DEBIAN-CVE-2021-38506 | Dec 8, 2021 |
| thunderbird · Debian 13.5 (trixie) | 1:91.3.0-1 | DEBIAN-CVE-2021-38506 | Dec 8, 2021 |
| thunderbird · Debian 14 | 1:91.3.0-1 | DEBIAN-CVE-2021-38506 | Dec 8, 2021 |
| thunderbird · RHEL 8 | 0:91.3.0-2.el8_4 | RHSA-2021:4130 | Nov 4, 2021 |
| thunderbird · Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | thunderbird 1:91.5.0+build1-0ubuntu0.18.04.1 | Feb 16, 2023 |
| thunderbird · Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | thunderbird 1:91.5.0+build1-0ubuntu0.20.04.1 | Feb 16, 2023 |
| thunderbird · Ubuntu 22.04.1 LTS (jammy) | 1:91.3.1+build1-0ubuntu1 | thunderbird 1:91.3.1+build1-0ubuntu1 | Nov 2, 2021 |
| thunderbird · ol 8 | 0:91.3.0-2.0.1.el8_4 | ELSA-2021-4130 | Nov 5, 2021 |
| thunderbird-gnome-support · Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | thunderbird-gnome-support 1:91.5.0+build1-0ubuntu0.18.04.1 | Feb 16, 2023 |
| thunderbird-gnome-support · Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | thunderbird-gnome-support 1:91.5.0+build1-0ubuntu0.20.04.1 | Feb 16, 2023 |
| thunderbird-gnome-support · Ubuntu 22.04.1 LTS (jammy) | 1:91.3.1+build1-0ubuntu1 | thunderbird-gnome-support 1:91.3.1+build1-0ubuntu1 | Nov 2, 2021 |
| thunderbird-mozsymbols · Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | thunderbird-mozsymbols 1:91.5.0+build1-0ubuntu0.18.04.1 | Feb 16, 2023 |
| thunderbird-mozsymbols · Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | thunderbird-mozsymbols 1:91.5.0+build1-0ubuntu0.20.04.1 | Feb 16, 2023 |
| thunderbird-mozsymbols · Ubuntu 22.04.1 LTS (jammy) | 1:91.3.1+build1-0ubuntu1 | thunderbird-mozsymbols 1:91.3.1+build1-0ubuntu1 | Nov 2, 2021 |
| xul-ext-calendar-timezones · Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | xul-ext-calendar-timezones 1:91.5.0+build1-0ubuntu0.18.04.1 | Feb 16, 2023 |
| xul-ext-calendar-timezones · Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | xul-ext-calendar-timezones 1:91.5.0+build1-0ubuntu0.20.04.1 | Feb 16, 2023 |
| xul-ext-calendar-timezones · Ubuntu 22.04.1 LTS (jammy) | 1:91.3.1+build1-0ubuntu1 | xul-ext-calendar-timezones 1:91.3.1+build1-0ubuntu1 | Nov 2, 2021 |
| xul-ext-gdata-provider · Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | xul-ext-gdata-provider 1:91.5.0+build1-0ubuntu0.18.04.1 | Feb 16, 2023 |
| xul-ext-gdata-provider · Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | xul-ext-gdata-provider 1:91.5.0+build1-0ubuntu0.20.04.1 | Feb 16, 2023 |
| xul-ext-gdata-provider · Ubuntu 22.04.1 LTS (jammy) | 1:91.3.1+build1-0ubuntu1 | xul-ext-gdata-provider 1:91.3.1+build1-0ubuntu1 | Nov 2, 2021 |
| xul-ext-lightning · Ubuntu 18.04.6 LTS (bionic) | 1:91.5.0+build1-0ubuntu0.18.04.1 | xul-ext-lightning 1:91.5.0+build1-0ubuntu0.18.04.1 | Feb 16, 2023 |
| xul-ext-lightning · Ubuntu 20.04 LTS (focal) | 1:91.5.0+build1-0ubuntu0.20.04.1 | xul-ext-lightning 1:91.5.0+build1-0ubuntu0.20.04.1 | Feb 16, 2023 |
| xul-ext-lightning · Ubuntu 22.04.1 LTS (jammy) | 1:91.3.1+build1-0ubuntu1 | xul-ext-lightning 1:91.3.1+build1-0ubuntu1 | Nov 2, 2021 |
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