CVE-2021-4128

Public Exploit

Description

When transitioning in and out of fullscreen mode, a graphics object was not correctly protected; resulting in memory corruption and a potentially exploitable crash.<br>*This bug only affects Firefox on MacOS. Other operating systems are unaffected.*. This vulnerability affects Firefox < 95.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.22%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-52/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1735852 patch exploit vendor advisory issue tracking

Frequently Asked Questions

What is the severity of CVE-2021-4128?
CVE-2021-4128 has been scored as a medium severity vulnerability.
How to fix CVE-2021-4128?
To fix CVE-2021-4128, 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-2021-4128 being actively exploited in the wild?
It is possible that CVE-2021-4128 is being exploited or will be exploited in a near future based on public information. 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-2021-4128?
CVE-2021-4128 affects Mozilla Firefox.
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