CVE-2021-29987

MediumCVSS 6.5/10Last modified Jun 17, 2026

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.

Metrics

CVSS 3.1 6.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Weakness enumeration

CWE-307

Affected software

Vendor	Product	Versions
Mozilla	Firefox	>= unspecified, < 91
Mozilla	Thunderbird	>= unspecified, < 91

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1716129Issue Tracking, Vendor Advisory
https://security.gentoo.org/glsa/202202-03Third Party Advisory
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=1716129Issue Tracking, Vendor Advisory
https://security.gentoo.org/glsa/202202-03Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2021-33/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-36/Vendor Advisory

Timeline

Published: Aug 17, 2021
Last modified: Jun 17, 2026
NVD status: Modified

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