CVE-2021-23975

Description

The developer page about:memory has a Measure function for exploring what object types the browser has allocated and their sizes. When this function was invoked we incorrectly called the sizeof function, instead of using the API method that checks for invalid pointers. This vulnerability affects Firefox < 86.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.21%
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/mfsa2021-07/ release notes vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1685145 vendor advisory issue tracking permissions required
https://security.gentoo.org/glsa/202104-10 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-23975?
CVE-2021-23975 has been scored as a medium severity vulnerability.
How to fix CVE-2021-23975?
To fix CVE-2021-23975, 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-2021-23975 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-23975 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-2021-23975?
CVE-2021-23975 affects Mozilla Firefox.
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