postfix — security advisory
The SMTP server in Postfix before 2.5.13, 2.6.x before 2.6.10, 2.7.x before 2.7.4, and 2.8.x before 2.8.3, when certain Cyrus SASL authentication methods are enabled, does not create a new server handle after client authentication fails, which allows remote attackers to cause a denial of service (heap memory corruption and daemon crash) or possibly execute arbitrary code via an invalid AUTH command with one method followed by an AUTH command with a different method.
- Products
- postfix
- Affected versions
- Not specified
- Fixed versions
- 2.8.3-1
- CVEs
- CVE-2011-1720
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 22:41 UTC · Revision 1
Source evidence
The SMTP server in Postfix before 2.5.13, 2.6.x before 2.6.10, 2.7.x before 2.7.4, and 2.8.x before 2.8.3, when certain Cyrus SASL authentication methods are enabled, does not create a new server handle after client authentication fails, which allows remote attackers to cause a denial of service (heap memory corruption and daemon crash) or possibly execute arbitrary code via an invalid AUTH command with one method followed by an AUTH command with a different method.
osv:DEBIAN-CVE-2011-1720
postfix
Fixed versions: 2.8.3-1
postfix
Fixed versions: 2.8.3-1
postfix
Fixed versions: 2.8.3-1
Complete source record
{
"id": "7f964da4e53a26c39ad078645ab6d53540e29954cfe912489179672f254d0c29",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2011-1720",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2011-1720",
"summary": "The SMTP server in Postfix before 2.5.13, 2.6.x before 2.6.10, 2.7.x before 2.7.4, and 2.8.x before 2.8.3, when certain Cyrus SASL authentication methods are enabled, does not create a new server handle after client authentication fails, which allows remote attackers to cause a denial of service (heap memory corruption and daemon crash) or possibly execute arbitrary code via an invalid AUTH command with one method followed by an AUTH command with a different method.",
"evidence": "osv:DEBIAN-CVE-2011-1720",
"products": [
{
"name": {
"value": "postfix",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.8.3-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.8.3-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.8.3-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "DEBIAN-CVE-2011-1720",
"aliases": [
"DEBIAN-CVE-2011-1720"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.8.3-1"
}
]
}
],
"package": {
"name": "postfix",
"purl": "pkg:deb/debian/postfix?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2011-1720.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.8.3-1"
}
]
}
],
"package": {
"name": "postfix",
"purl": "pkg:deb/debian/postfix?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2011-1720.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.8.3-1"
}
]
}
],
"package": {
"name": "postfix",
"purl": "pkg:deb/debian/postfix?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2011-1720.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T17:47:28.129333332Z",
"provider": "osv",
"upstream": [
"CVE-2011-1720"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2011-1720"
]
},
"related_cves": [
{
"value": "CVE-2011-1720",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 417075,
"published_at": "2011-05-13T17:05:43.207+00:00"
}