CVE-2021-38506

Description

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.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.21%
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 Firefox
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox ESR
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-49/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-50/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-48/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1730750 vendor advisory issue tracking permissions required
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-2021-38506?
CVE-2021-38506 has been scored as a medium severity vulnerability.
How to fix CVE-2021-38506?
To fix CVE-2021-38506, 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-2021-38506 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-38506 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-2021-38506?
CVE-2021-38506 affects Mozilla Firefox, Mozilla Thunderbird, Mozilla Firefox ESR.
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