CVE-2021-43528

Description

Thunderbird unexpectedly enabled JavaScript in the composition area. The JavaScript execution context was limited to this area and did not receive chrome-level privileges, but could be used as a stepping stone to further an attack with other vulnerabilities. This vulnerability affects Thunderbird < 91.4.0.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.30%
Vendor Advisory debian.org Vendor Advisory gentoo.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Thunderbird
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-54/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1742579 issue tracking permissions required vendor advisory broken link
https://www.debian.org/security/2022/dsa-5034 issue tracking third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html third party advisory mailing list
https://security.gentoo.org/glsa/202208-14 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-43528?
CVE-2021-43528 has been scored as a medium severity vulnerability.
How to fix CVE-2021-43528?
To fix CVE-2021-43528, 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-2021-43528 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43528 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-2021-43528?
CVE-2021-43528 affects Mozilla Thunderbird.
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