mutt — security advisory
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.
- Products
- mutt
- Affected versions
- Not specified
- Fixed versions
- 2.0.5-1
- CVEs
- CVE-2021-3181
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 00:34 UTC · Revision 1
Source evidence
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.
osv:DEBIAN-CVE-2021-3181
mutt
Fixed versions: 2.0.5-1
mutt
Fixed versions: 2.0.5-1
mutt
Fixed versions: 2.0.5-1
Complete source record
{
"id": "87f0876418dbeb68cc07e70dd65afa2550895166c7c84b1931b35065c11f3a46",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-3181",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-3181",
"summary": "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.",
"evidence": "osv:DEBIAN-CVE-2021-3181",
"products": [
{
"name": {
"value": "mutt",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.0.5-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "mutt",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.0.5-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "mutt",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.0.5-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2021-3181",
"aliases": [
"DEBIAN-CVE-2021-3181"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.0.5-1"
}
]
}
],
"package": {
"name": "mutt",
"purl": "pkg:deb/debian/mutt?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-3181.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.0.5-1"
}
]
}
],
"package": {
"name": "mutt",
"purl": "pkg:deb/debian/mutt?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-3181.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.0.5-1"
}
]
}
],
"package": {
"name": "mutt",
"purl": "pkg:deb/debian/mutt?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-3181.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:03:26.474529482Z",
"provider": "osv",
"upstream": [
"CVE-2021-3181"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-3181"
]
},
"related_cves": [
{
"value": "CVE-2021-3181",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 421519,
"published_at": "2021-01-19T15:15:12.327+00:00"
}