Medium severity · published Jan 19, 2021
CVE-2021-3181
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…
6.5
CVSS
2.8%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.8% · higher than 87% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
FE
Fedora · Fedoraproject
32; 33 · source: NVD
MU
Mutt · Mutt
through 2.0.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3181
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3181
Mailing List
http://www.openwall.com/lists/oss-security/2021/01/19/10
Mailing List
http://www.openwall.com/lists/oss-security/2021/01/27/3
Patch
https://gitlab.com/muttmua/mutt/-/commit/4a2becbdb4422aaffe3ce314991b9d670b7adf17
Patch
https://gitlab.com/muttmua/mutt/-/commit/939b02b33ae29bc0d642570c1dcfd4b339037d19
Patch
https://gitlab.com/muttmua/mutt/-/commit/d4305208955c5cdd9fe96dfa61e7c1e14e176a14
Third Party Advisory
https://gitlab.com/muttmua/mutt/-/issues/323
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