CVE-2021-29955

Description

A transient execution vulnerability, named Floating Point Value Injection (FPVI) allowed an attacker to leak arbitrary memory addresses and may have also enabled JIT type confusion attacks. (A related vulnerability, Speculative Code Store Bypass (SCSB), did not affect Firefox.). This vulnerability affects Firefox ESR < 78.9 and Firefox < 87.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.46% Top 25%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox ESR
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-10/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-11/ release notes vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1692972 vendor advisory permissions required

Frequently Asked Questions

What is the severity of CVE-2021-29955?
CVE-2021-29955 has been scored as a medium severity vulnerability.
How to fix CVE-2021-29955?
To fix CVE-2021-29955, 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-2021-29955 being actively exploited in the wild?
It is possible that CVE-2021-29955 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-29955?
CVE-2021-29955 affects Mozilla Firefox ESR, Mozilla Firefox.
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