CVE-2021-44143

Description

A flaw was found in mbsync in isync 1.4.0 through 1.4.3. Due to an unchecked condition, a malicious or compromised IMAP server could use a crafted mail message that lacks headers (i.e., one that starts with an empty line) to provoke a heap overflow, which could conceivably be exploited for remote code execution.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 4.68% Top 15%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=999804 third party advisory
https://sourceforge.net/p/isync/isync/ref/master/tags/ third party advisory
https://sourceforge.net/p/isync/isync/commit_browser third party advisory patch
http://www.openwall.com/lists/oss-security/2021/12/03/2 mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CYZ2GNB4ZO2T27D2XNUWMCS3THZYSJQU/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LCBSY7OZ57XNC6ZYXF6WU5KBSWITZVDX/ vendor advisory
https://security.gentoo.org/glsa/202208-15 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-44143?
CVE-2021-44143 has been scored as a critical severity vulnerability.
How to fix CVE-2021-44143?
To fix CVE-2021-44143, 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-2021-44143 being actively exploited in the wild?
It is possible that CVE-2021-44143 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~5% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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