CVE-2021-3181
MEDIUM
Published Jan 19, 20215y ago · Modified Jun 17, 20262w ago
6.5 CVSS 3.1
Published Jan 19, 2021 5y ago
Last Modified Jun 17, 2026 2w ago
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 Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction Required
Scope Unchanged
Confidentiality None
Integrity None
Availability High
Threat Intelligence
No active exploitation signals — not in CISA KEV and no EPSS score yet.
Exploit & Patch Status
No Known Exploit
Patch Available
Weaknesses 1
CWE-401
Affected Products 5
| Vendor | Product | Version | Range |
|---|---|---|---|
| mutt | mutt | * | ≤2.0.4 |
| debian | debian_linux | 9.0 | any |
| debian | debian_linux | 10.0 | any |
| fedoraproject | fedora | 32 | any |
| fedoraproject | fedora | 33 | any |
References 11
- openwall.com http://www.openwall.com/lists/oss-security/2021/01/19/10
- openwall.com http://www.openwall.com/lists/oss-security/2021/01/27/3
- gitlab.com https://gitlab.com/muttmua/mutt/-/commit/4a2becbdb4422aaffe3ce314991b9d670b7adf17
- gitlab.com https://gitlab.com/muttmua/mutt/-/commit/939b02b33ae29bc0d642570c1dcfd4b339037d19
- gitlab.com https://gitlab.com/muttmua/mutt/-/commit/d4305208955c5cdd9fe96dfa61e7c1e14e176a14
- gitlab.com https://gitlab.com/muttmua/mutt/-/issues/323
- lists.debian.org https://lists.debian.org/debian-lts-announce/2021/01/msg00017.html
- lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DXGWXFO77HBCD3VYEIYHHYU33LYWWWNQ/
- lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/P2OMLQKAOHPYQA4GI7ZUO6UKCPUHLYO7/
- security.gentoo.org https://security.gentoo.org/glsa/202101-25
- debian.org https://www.debian.org/security/2021/dsa-4838
Remediation
- gitlab.com https://gitlab.com/muttmua/mutt/-/commit/4a2becbdb4422aaffe3ce314991b9d670b7adf17
- gitlab.com https://gitlab.com/muttmua/mutt/-/commit/939b02b33ae29bc0d642570c1dcfd4b339037d19
- gitlab.com https://gitlab.com/muttmua/mutt/-/commit/d4305208955c5cdd9fe96dfa61e7c1e14e176a14