UnratedFix available
dovecot: Fix of CVE-2026-27858
Type: advisorySources: OSV
- CVE-2026-27858: fix pre-auth memory exhaustion in managesieve-login from an oversized AUTHENTICATE initial response
- Products
- dovecot, dovecot-devel, dovecot-mysql, dovecot-pgsql, dovecot-pigeonhole
- Affected versions
- Not specified
- Fixed versions
- 1:2.2.36-8.el7.tuxcare.els3
- CVEs
- CVE-2026-27858
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 11:35 UTC · Revision 1
Source evidence
- CVE-2026-27858: fix pre-auth memory exhaustion in managesieve-login from an oversized AUTHENTICATE initial response
osv:CLSA-2026-1787232011
dovecot
Fixed versions: 1:2.2.36-8.el7.tuxcare.els3
dovecot-devel
Fixed versions: 1:2.2.36-8.el7.tuxcare.els3
dovecot-mysql
Fixed versions: 1:2.2.36-8.el7.tuxcare.els3
dovecot-pgsql
Fixed versions: 1:2.2.36-8.el7.tuxcare.els3
dovecot-pigeonhole
Fixed versions: 1:2.2.36-8.el7.tuxcare.els3
Complete source record
{
"id": "1f46f8a81a12d16dd23eeb2d42d53ae6a39786292de5279f8c9b1bb3c3ca17a7",
"url": "https://osv.dev/vulnerability/CLSA-2026-1787232011",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "dovecot: Fix of CVE-2026-27858",
"summary": "- CVE-2026-27858: fix pre-auth memory exhaustion in managesieve-login from an oversized AUTHENTICATE initial response",
"evidence": "osv:CLSA-2026-1787232011",
"products": [
{
"name": {
"value": "dovecot",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.2.36-8.el7.tuxcare.els3",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "dovecot-devel",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.2.36-8.el7.tuxcare.els3",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "dovecot-mysql",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.2.36-8.el7.tuxcare.els3",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "dovecot-pgsql",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.2.36-8.el7.tuxcare.els3",
"evidence": "/affected/3/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "dovecot-pigeonhole",
"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.2.36-8.el7.tuxcare.els3",
"evidence": "/affected/4/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "CLSA-2026-1787232011",
"aliases": [
"CLSA-2026-1787232011"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.2.36-8.el7.tuxcare.els3"
}
]
}
],
"package": {
"name": "dovecot",
"purl": "pkg:rpm/tuxcare/dovecot?distro=rhel-7",
"ecosystem": "TuxCare:RHEL:7"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1787232011.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.2.36-8.el7.tuxcare.els3"
}
]
}
],
"package": {
"name": "dovecot-devel",
"purl": "pkg:rpm/tuxcare/dovecot-devel?distro=rhel-7",
"ecosystem": "TuxCare:RHEL:7"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1787232011.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.2.36-8.el7.tuxcare.els3"
}
]
}
],
"package": {
"name": "dovecot-mysql",
"purl": "pkg:rpm/tuxcare/dovecot-mysql?distro=rhel-7",
"ecosystem": "TuxCare:RHEL:7"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1787232011.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.2.36-8.el7.tuxcare.els3"
}
]
}
],
"package": {
"name": "dovecot-pgsql",
"purl": "pkg:rpm/tuxcare/dovecot-pgsql?distro=rhel-7",
"ecosystem": "TuxCare:RHEL:7"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1787232011.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.2.36-8.el7.tuxcare.els3"
}
]
}
],
"package": {
"name": "dovecot-pigeonhole",
"purl": "pkg:rpm/tuxcare/dovecot-pigeonhole?distro=rhel-7",
"ecosystem": "TuxCare:RHEL:7"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1787232011.json"
}
}
],
"modified": "2026-10-26T09:31:58.419105184Z",
"provider": "osv",
"upstream": [
"CVE-2026-27858"
],
"references": [
"https://errata.tuxcare.com/els_os/rhel7els/CLSA-2026-1787232011.html",
"https://nvd.nist.gov/vuln/detail/CVE-2026-27858"
]
},
"related_cves": [
{
"value": "CVE-2026-27858",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 449207,
"published_at": "2026-08-20T13:20:21+00:00"
}