CVE-2021-29987

Description

After requesting multiple permissions, and closing the first permission panel, subsequent permission panels will be displayed in a different position but still record a click in the default location, making it possible to trick a user into accepting a permission they did not want to. *This bug only affects Firefox on Linux. Other operating systems are unaffected.*. This vulnerability affects Firefox < 91 and Thunderbird < 91.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.31%
Vendor Advisory gentoo.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Affected: Mozilla Thunderbird
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-33/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-36/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1716129 issue tracking vendor advisory
https://security.gentoo.org/glsa/202202-03 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-29987?
CVE-2021-29987 has been scored as a medium severity vulnerability.
How to fix CVE-2021-29987?
To fix CVE-2021-29987, 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-2021-29987 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-29987 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-2021-29987?
CVE-2021-29987 affects Mozilla Firefox, Mozilla Thunderbird.
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