CVE-2021-43537

Description

An incorrect type conversion of sizes from 64bit to 32bit integers allowed an attacker to corrupt memory leading to a potentially exploitable crash. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.60%
Vendor Advisory debian.org Vendor Advisory debian.org Vendor Advisory gentoo.org Vendor Advisory gentoo.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/mfsa2021-53/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-54/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-52/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1738237 vendor advisory issue tracking
https://www.debian.org/security/2021/dsa-5026 vendor advisory mailing list third party advisory
https://lists.debian.org/debian-lts-announce/2021/12/msg00030.html third party advisory mailing list
https://www.debian.org/security/2022/dsa-5034 vendor advisory mailing list third party advisory
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html third party advisory mailing list
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-2021-43537?
CVE-2021-43537 has been scored as a high severity vulnerability.
How to fix CVE-2021-43537?
To fix CVE-2021-43537, 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-2021-43537 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43537 is being actively exploited. 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-2021-43537?
CVE-2021-43537 affects Mozilla Thunderbird, Mozilla Firefox ESR, Mozilla Firefox.
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