CVE-2021-29984

Public Exploit

Description

Instruction reordering resulted in a sequence of instructions that would cause an object to be incorrectly considered during garbage collection. This led to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.13, Thunderbird < 91, Firefox ESR < 78.13, and Firefox < 91.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.22%
Vendor Advisory gentoo.org Vendor Advisory gentoo.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox ESR
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-33/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-35/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-34/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-36/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1720031 issue tracking exploit vendor advisory
https://security.gentoo.org/glsa/202202-03 third party advisory vendor advisory
https://security.gentoo.org/glsa/202208-14 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-29984?
CVE-2021-29984 has been scored as a high severity vulnerability.
How to fix CVE-2021-29984?
To fix CVE-2021-29984, 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-2021-29984 being actively exploited in the wild?
It is possible that CVE-2021-29984 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-2021-29984?
CVE-2021-29984 affects Mozilla Thunderbird, Mozilla Firefox ESR, Mozilla Firefox.
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