CVE-2021-29961

Description

When styling and rendering an oversized `<select>` element, Firefox did not apply correct clipping which allowed an attacker to paint over the user interface. This vulnerability affects Firefox < 89.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.32%
Vendor Advisory gentoo.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-23/ release notes vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1700235 issue tracking vendor advisory broken link
https://security.gentoo.org/glsa/202107-09 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-29961?
CVE-2021-29961 has been scored as a medium severity vulnerability.
How to fix CVE-2021-29961?
To fix CVE-2021-29961, 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-2021-29961 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-29961 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-2021-29961?
CVE-2021-29961 affects Mozilla Firefox.
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