dovecot — security advisory
An attacker that has valid credentials can open many connections to the imap-hibernate service and send invalid commands, which can intermittently cause an out-of-bounds read and crash the process. The crash interrupts hibernated IMAP sessions handled by the affected process, which can cause degradation of service for IMAP. Disable IMAP hibernation. Update to non-vulnerable version. No publicly available exploits are known.
- Products
- dovecot
- Affected versions
- 1:2.3.19.1+dfsg1-2.1, 1:2.3.19.1+dfsg1-2.1+deb12u1, 1:2.3.19.1+dfsg1-2.1+deb12u2, 1:2.3.19.1+dfsg1-2.1+deb12u3, 1:2.3.19.1+dfsg1-2.1+deb12u4, 1:2.3.19.1+dfsg1-2.1+deb12u5, 1:2.3.19.1+dfsg1-2.1+deb12u6, 1:2.4.1+dfsg1-6, 1:2.4.1+dfsg1-6+deb13u1, 1:2.4.1+dfsg1-6+deb13u2, 1:2.4.1+dfsg1-6+deb13u3, 1:2.4.1+dfsg1-6+deb13u4, 1:2.4.1+dfsg1-6+deb13u5, 1:2.4.1+dfsg1-6+deb13u6, 1:2.4.1+dfsg1-7, 1:2.4.1+dfsg1-8, 1:2.4.1+dfsg1-9, 1:2.4.2+dfsg1-1, 1:2.4.2+dfsg1-2, 1:2.4.2+dfsg1-3, 1:2.4.2+dfsg1-4, 1:2.4.3+dfsg1-1, 1:2.4.3+dfsg1-2, 1:2.4.4+dfsg1-1, 1:2.4.4+dfsg1-2
- Fixed versions
- 1:2.3.19.1+dfsg1-2.1+deb12u7, 1:2.4.1+dfsg1-6+deb13u7, 1:2.4.5+dfsg1-1
- CVEs
- CVE-2026-40015
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 03:15 UTC · Revision 1
Source evidence
An attacker that has valid credentials can open many connections to the imap-hibernate service and send invalid commands, which can intermittently cause an out-of-bounds read and crash the process. The crash interrupts hibernated IMAP sessions handled by the affected process, which can cause degradation of service for IMAP. Disable IMAP hibernation. Update to non-vulnerable version. No publicly available exploits are known.
osv:DEBIAN-CVE-2026-40015
dovecot
Fixed versions: 1:2.3.19.1+dfsg1-2.1+deb12u7
dovecot
Fixed versions: 1:2.4.1+dfsg1-6+deb13u7
dovecot
Fixed versions: 1:2.4.5+dfsg1-1
Complete source record
{
"id": "28a7ed8ad1fc4ce8398e450561d8994a208e264f9235aea6be6c9ff255b014e5",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-40015",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-40015",
"summary": "An attacker that has valid credentials can open many connections to the imap-hibernate service and send invalid commands, which can intermittently cause an out-of-bounds read and crash the process. The crash interrupts hibernated IMAP sessions handled by the affected process, which can cause degradation of service for IMAP. Disable IMAP hibernation. Update to non-vulnerable version. No publicly available exploits are known.",
"evidence": "osv:DEBIAN-CVE-2026-40015",
"products": [
{
"name": {
"value": "dovecot",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.3.19.1+dfsg1-2.1+deb12u7",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "1:2.3.19.1+dfsg1-2.1",
"evidence": "/affected/0/versions"
},
{
"value": "1:2.3.19.1+dfsg1-2.1+deb12u1",
"evidence": "/affected/0/versions"
},
{
"value": "1:2.3.19.1+dfsg1-2.1+deb12u2",
"evidence": "/affected/0/versions"
},
{
"value": "1:2.3.19.1+dfsg1-2.1+deb12u3",
"evidence": "/affected/0/versions"
},
{
"value": "1:2.3.19.1+dfsg1-2.1+deb12u4",
"evidence": "/affected/0/versions"
},
{
"value": "1:2.3.19.1+dfsg1-2.1+deb12u5",
"evidence": "/affected/0/versions"
},
{
"value": "1:2.3.19.1+dfsg1-2.1+deb12u6",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "dovecot",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.4.1+dfsg1-6+deb13u7",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": [
{
"value": "1:2.4.1+dfsg1-6",
"evidence": "/affected/1/versions"
},
{
"value": "1:2.4.1+dfsg1-6+deb13u1",
"evidence": "/affected/1/versions"
},
{
"value": "1:2.4.1+dfsg1-6+deb13u2",
"evidence": "/affected/1/versions"
},
{
"value": "1:2.4.1+dfsg1-6+deb13u3",
"evidence": "/affected/1/versions"
},
{
"value": "1:2.4.1+dfsg1-6+deb13u4",
"evidence": "/affected/1/versions"
},
{
"value": "1:2.4.1+dfsg1-6+deb13u5",
"evidence": "/affected/1/versions"
},
{
"value": "1:2.4.1+dfsg1-6+deb13u6",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "dovecot",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.4.5+dfsg1-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "1:2.4.1+dfsg1-6",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.1+dfsg1-7",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.1+dfsg1-8",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.1+dfsg1-9",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.2+dfsg1-1",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.2+dfsg1-2",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.2+dfsg1-3",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.2+dfsg1-4",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.3+dfsg1-1",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.3+dfsg1-2",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.4+dfsg1-1",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.4.4+dfsg1-2",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2026-40015",
"aliases": [
"DEBIAN-CVE-2026-40015"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.3.19.1+dfsg1-2.1+deb12u7"
}
]
}
],
"package": {
"name": "dovecot",
"purl": "pkg:deb/debian/dovecot?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"1:2.3.19.1+dfsg1-2.1",
"1:2.3.19.1+dfsg1-2.1+deb12u1",
"1:2.3.19.1+dfsg1-2.1+deb12u2",
"1:2.3.19.1+dfsg1-2.1+deb12u3",
"1:2.3.19.1+dfsg1-2.1+deb12u4",
"1:2.3.19.1+dfsg1-2.1+deb12u5",
"1:2.3.19.1+dfsg1-2.1+deb12u6"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-40015.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.4.1+dfsg1-6+deb13u7"
}
]
}
],
"package": {
"name": "dovecot",
"purl": "pkg:deb/debian/dovecot?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1:2.4.1+dfsg1-6",
"1:2.4.1+dfsg1-6+deb13u1",
"1:2.4.1+dfsg1-6+deb13u2",
"1:2.4.1+dfsg1-6+deb13u3",
"1:2.4.1+dfsg1-6+deb13u4",
"1:2.4.1+dfsg1-6+deb13u5",
"1:2.4.1+dfsg1-6+deb13u6"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-40015.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.4.5+dfsg1-1"
}
]
}
],
"package": {
"name": "dovecot",
"purl": "pkg:deb/debian/dovecot?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1:2.4.1+dfsg1-6",
"1:2.4.1+dfsg1-7",
"1:2.4.1+dfsg1-8",
"1:2.4.1+dfsg1-9",
"1:2.4.2+dfsg1-1",
"1:2.4.2+dfsg1-2",
"1:2.4.2+dfsg1-3",
"1:2.4.2+dfsg1-4",
"1:2.4.3+dfsg1-1",
"1:2.4.3+dfsg1-2",
"1:2.4.4+dfsg1-1",
"1:2.4.4+dfsg1-2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-40015.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-31T16:04:23.081226636Z",
"provider": "osv",
"upstream": [
"CVE-2026-40015"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-40015"
]
},
"related_cves": [
{
"value": "CVE-2026-40015",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 427028,
"published_at": "2026-08-28T12:16:28.363+00:00"
}