CVE-2021-43538

Description

By misusing a race in our notification code, an attacker could have forcefully hidden the notification for pages that had received full screen and pointer lock access, which could have been used for spoofing attacks. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.19%
Vendor Advisory debian.org Vendor Advisory debian.org Vendor Advisory gentoo.org Vendor Advisory gentoo.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox ESR
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-53/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-54/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-52/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1739091 issue tracking permissions required vendor advisory
https://www.debian.org/security/2021/dsa-5026 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2021/12/msg00030.html third party advisory mailing list
https://www.debian.org/security/2022/dsa-5034 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html third party advisory mailing list
https://security.gentoo.org/glsa/202202-03 third party advisory vendor advisory
https://security.gentoo.org/glsa/202208-14 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-43538?
CVE-2021-43538 has been scored as a medium severity vulnerability.
How to fix CVE-2021-43538?
To fix CVE-2021-43538, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43538 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43538 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43538?
CVE-2021-43538 affects Mozilla Thunderbird, Mozilla Firefox ESR, Mozilla Firefox.
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