CVE-2021-3181

Description

rfc822.c in Mutt through 2.0.4 allows remote attackers to cause a denial of service (mailbox unavailability) by sending email messages with sequences of semicolon characters in RFC822 address fields (aka terminators of empty groups). A small email message from the attacker can cause large memory consumption, and the victim may then be unable to see email messages from other persons.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 2.54% Top 20%
Vendor Advisory gentoo.org Vendor Advisory debian.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://gitlab.com/muttmua/mutt/-/issues/323 third party advisory
https://gitlab.com/muttmua/mutt/-/commit/4a2becbdb4422aaffe3ce314991b9d670b7adf17 third party advisory patch
https://gitlab.com/muttmua/mutt/-/commit/939b02b33ae29bc0d642570c1dcfd4b339037d19 third party advisory patch
https://gitlab.com/muttmua/mutt/-/commit/d4305208955c5cdd9fe96dfa61e7c1e14e176a14 third party advisory patch
http://www.openwall.com/lists/oss-security/2021/01/19/10 third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2021/01/msg00017.html third party advisory mailing list
https://security.gentoo.org/glsa/202101-25 third party advisory vendor advisory
https://www.debian.org/security/2021/dsa-4838 third party advisory vendor advisory
http://www.openwall.com/lists/oss-security/2021/01/27/3 third party advisory mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/P2OMLQKAOHPYQA4GI7ZUO6UKCPUHLYO7/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DXGWXFO77HBCD3VYEIYHHYU33LYWWWNQ/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-3181?
CVE-2021-3181 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3181?
To fix CVE-2021-3181, 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-2021-3181 being actively exploited in the wild?
It is possible that CVE-2021-3181 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~3% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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