Medium
cyrus-imapd — security advisory
An issue was discovered in Cyrus IMAP before 3.12.4. There is a Sieve mailbox existence oracle. An authenticated user could install a Sieve script that probed whether another user's private mailbox existed, or read the value of shared mailbox annotations, by observing which fileinto branch fired during LMTP delivery.
- Products
- cyrus-imapd
- Affected versions
- 2.5.10-3build1, 2.5.10-3build2, 2.5.10-3ubuntu1, 2.5.10-3ubuntu1.1, 2.5.10-3ubuntu1.1+esm1, 3.0.11-1, 3.0.11-1build1, 3.0.12-1, 3.0.12-2, 3.0.12-2ubuntu2, 3.0.12-2ubuntu3, 3.0.13-2ubuntu1, 3.0.13-3ubuntu1, 3.0.13-4ubuntu1, 3.0.13-5, 3.0.13-5ubuntu0.1~esm1, 3.0.13-5ubuntu0.1~esm2, 3.10.2-1, 3.12.1-2, 3.12.1-2build1, 3.12.1-3, 3.12.2-1, 3.12.2-1build1, 3.12.3-3build1, 3.2.6-2build1, 3.4.2-2, 3.4.2-2build1, 3.4.3-2, 3.4.3-3, 3.4.3-3build2, 3.4.3-3ubuntu0.1, 3.4.3-3ubuntu0.1+esm1, 3.4.3-3ubuntu0.3, 3.4.3-3ubuntu0.3+esm1, 3.8.0-5, 3.8.1-1, 3.8.1-1build1, 3.8.1-1build2, 3.8.1-3, 3.8.1-3build3, 3.8.2-1, 3.8.2-1ubuntu0.1~esm1, 3.8.2-1ubuntu0.2, 3.8.2-1ubuntu0.2+esm1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-61911
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:49 UTC · Revision 1
Source evidence
An issue was discovered in Cyrus IMAP before 3.12.4. There is a Sieve mailbox existence oracle. An authenticated user could install a Sieve script that probed whether another user's private mailbox existed, or read the value of shared mailbox annotations, by observing which fileinto branch fired during LMTP delivery.
osv:UBUNTU-CVE-2026-61911
cyrus-imapd
Fixed versions: Not specified
cyrus-imapd
Fixed versions: Not specified
cyrus-imapd
Fixed versions: Not specified
cyrus-imapd
Fixed versions: Not specified
cyrus-imapd
Fixed versions: Not specified
cyrus-imapd
Fixed versions: Not specified
Complete source record
{
"id": "ddb8118b5ab906b896940445be7721a34ee1d8a51e11ea937292d043ea189e71",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-61911",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-61911",
"summary": "An issue was discovered in Cyrus IMAP before 3.12.4. There is a Sieve mailbox existence oracle. An authenticated user could install a Sieve script that probed whether another user's private mailbox existed, or read the value of shared mailbox annotations, by observing which fileinto branch fired during LMTP delivery.",
"evidence": "osv:UBUNTU-CVE-2026-61911",
"products": [
{
"name": {
"value": "cyrus-imapd",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.5.10-3build1",
"evidence": "/affected/0/versions"
},
{
"value": "2.5.10-3build2",
"evidence": "/affected/0/versions"
},
{
"value": "2.5.10-3ubuntu1",
"evidence": "/affected/0/versions"
},
{
"value": "2.5.10-3ubuntu1.1",
"evidence": "/affected/0/versions"
},
{
"value": "2.5.10-3ubuntu1.1+esm1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "cyrus-imapd",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.0.11-1",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.11-1build1",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.12-1",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.12-2",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.12-2ubuntu2",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.12-2ubuntu3",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.13-2ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.13-3ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.13-4ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.13-5",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.13-5ubuntu0.1~esm1",
"evidence": "/affected/1/versions"
},
{
"value": "3.0.13-5ubuntu0.1~esm2",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "cyrus-imapd",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.2.6-2build1",
"evidence": "/affected/2/versions"
},
{
"value": "3.4.2-2",
"evidence": "/affected/2/versions"
},
{
"value": "3.4.2-2build1",
"evidence": "/affected/2/versions"
},
{
"value": "3.4.3-2",
"evidence": "/affected/2/versions"
},
{
"value": "3.4.3-3",
"evidence": "/affected/2/versions"
},
{
"value": "3.4.3-3build2",
"evidence": "/affected/2/versions"
},
{
"value": "3.4.3-3ubuntu0.1",
"evidence": "/affected/2/versions"
},
{
"value": "3.4.3-3ubuntu0.1+esm1",
"evidence": "/affected/2/versions"
},
{
"value": "3.4.3-3ubuntu0.3",
"evidence": "/affected/2/versions"
},
{
"value": "3.4.3-3ubuntu0.3+esm1",
"evidence": "/affected/2/versions"
}
]
},
{
"name": {
"value": "cyrus-imapd",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.8.0-5",
"evidence": "/affected/3/versions"
},
{
"value": "3.8.1-1",
"evidence": "/affected/3/versions"
},
{
"value": "3.8.1-1build1",
"evidence": "/affected/3/versions"
},
{
"value": "3.8.1-1build2",
"evidence": "/affected/3/versions"
},
{
"value": "3.8.1-3",
"evidence": "/affected/3/versions"
},
{
"value": "3.8.1-3build3",
"evidence": "/affected/3/versions"
},
{
"value": "3.8.2-1",
"evidence": "/affected/3/versions"
},
{
"value": "3.8.2-1ubuntu0.1~esm1",
"evidence": "/affected/3/versions"
},
{
"value": "3.8.2-1ubuntu0.2",
"evidence": "/affected/3/versions"
},
{
"value": "3.8.2-1ubuntu0.2+esm1",
"evidence": "/affected/3/versions"
}
]
},
{
"name": {
"value": "cyrus-imapd",
"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.12.1-3",
"evidence": "/affected/4/versions"
},
{
"value": "3.12.2-1",
"evidence": "/affected/4/versions"
},
{
"value": "3.12.2-1build1",
"evidence": "/affected/4/versions"
},
{
"value": "3.12.3-3build1",
"evidence": "/affected/4/versions"
}
]
},
{
"name": {
"value": "cyrus-imapd",
"evidence": "/affected/5/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.10.2-1",
"evidence": "/affected/5/versions"
},
{
"value": "3.12.1-2",
"evidence": "/affected/5/versions"
},
{
"value": "3.12.1-2build1",
"evidence": "/affected/5/versions"
},
{
"value": "3.12.1-3",
"evidence": "/affected/5/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "UBUNTU-CVE-2026-61911",
"aliases": [
"UBUNTU-CVE-2026-61911"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "cyrus-imapd",
"purl": "pkg:deb/ubuntu/cyrus-imapd?arch=source&distro=esm-apps%2Fbionic",
"ecosystem": "Ubuntu:Pro:18.04:LTS"
},
"versions": [
"2.5.10-3build1",
"2.5.10-3build2",
"2.5.10-3ubuntu1",
"2.5.10-3ubuntu1.1",
"2.5.10-3ubuntu1.1+esm1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-61911.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "cyrus-admin",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
},
{
"binary_name": "cyrus-caldav",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
},
{
"binary_name": "cyrus-clients",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
},
{
"binary_name": "cyrus-common",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
},
{
"binary_name": "cyrus-imapd",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
},
{
"binary_name": "cyrus-murder",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
},
{
"binary_name": "cyrus-nntpd",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
},
{
"binary_name": "cyrus-pop3d",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
},
{
"binary_name": "cyrus-replication",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
},
{
"binary_name": "libcyrus-imap-perl",
"binary_version": "2.5.10-3ubuntu1.1+esm1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "cyrus-imapd",
"purl": "pkg:deb/ubuntu/cyrus-imapd?arch=source&distro=esm-apps%2Ffocal",
"ecosystem": "Ubuntu:Pro:20.04:LTS"
},
"versions": [
"3.0.11-1",
"3.0.11-1build1",
"3.0.12-1",
"3.0.12-2",
"3.0.12-2ubuntu2",
"3.0.12-2ubuntu3",
"3.0.13-2ubuntu1",
"3.0.13-3ubuntu1",
"3.0.13-4ubuntu1",
"3.0.13-5",
"3.0.13-5ubuntu0.1~esm1",
"3.0.13-5ubuntu0.1~esm2"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-61911.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "cyrus-admin",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
},
{
"binary_name": "cyrus-caldav",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
},
{
"binary_name": "cyrus-clients",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
},
{
"binary_name": "cyrus-common",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
},
{
"binary_name": "cyrus-imapd",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
},
{
"binary_name": "cyrus-murder",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
},
{
"binary_name": "cyrus-nntpd",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
},
{
"binary_name": "cyrus-pop3d",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
},
{
"binary_name": "cyrus-replication",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
},
{
"binary_name": "libcyrus-imap-perl",
"binary_version": "3.0.13-5ubuntu0.1~esm2"
}
]
}
},
{
"ranges": [
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"events": [
{
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}
]
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],
"package": {
"name": "cyrus-imapd",
"purl": "pkg:deb/ubuntu/cyrus-imapd?arch=source&distro=esm-apps%2Fjammy",
"ecosystem": "Ubuntu:Pro:22.04:LTS"
},
"versions": [
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"3.4.2-2",
"3.4.2-2build1",
"3.4.3-2",
"3.4.3-3",
"3.4.3-3build2",
"3.4.3-3ubuntu0.1",
"3.4.3-3ubuntu0.1+esm1",
"3.4.3-3ubuntu0.3",
"3.4.3-3ubuntu0.3+esm1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-61911.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "cyrus-admin",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
},
{
"binary_name": "cyrus-caldav",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
},
{
"binary_name": "cyrus-clients",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
},
{
"binary_name": "cyrus-common",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
},
{
"binary_name": "cyrus-imapd",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
},
{
"binary_name": "cyrus-murder",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
},
{
"binary_name": "cyrus-nntpd",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
},
{
"binary_name": "cyrus-pop3d",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
},
{
"binary_name": "cyrus-replication",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
},
{
"binary_name": "libcyrus-imap-perl",
"binary_version": "3.4.3-3ubuntu0.3+esm1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "cyrus-imapd",
"purl": "pkg:deb/ubuntu/cyrus-imapd?arch=source&distro=esm-apps%2Fnoble",
"ecosystem": "Ubuntu:Pro:24.04:LTS"
},
"versions": [
"3.8.0-5",
"3.8.1-1",
"3.8.1-1build1",
"3.8.1-1build2",
"3.8.1-3",
"3.8.1-3build3",
"3.8.2-1",
"3.8.2-1ubuntu0.1~esm1",
"3.8.2-1ubuntu0.2",
"3.8.2-1ubuntu0.2+esm1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-61911.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "cyrus-admin",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
},
{
"binary_name": "cyrus-caldav",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
},
{
"binary_name": "cyrus-clients",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
},
{
"binary_name": "cyrus-common",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
},
{
"binary_name": "cyrus-imapd",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
},
{
"binary_name": "cyrus-murder",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
},
{
"binary_name": "cyrus-nntpd",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
},
{
"binary_name": "cyrus-pop3d",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
},
{
"binary_name": "cyrus-replication",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
},
{
"binary_name": "libcyrus-imap-perl",
"binary_version": "3.8.2-1ubuntu0.2+esm1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "cyrus-imapd",
"purl": "pkg:deb/ubuntu/cyrus-imapd?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"3.12.1-3",
"3.12.2-1",
"3.12.2-1build1",
"3.12.3-3build1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-61911.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "cyrus-admin",
"binary_version": "3.12.3-3build1"
},
{
"binary_name": "cyrus-caldav",
"binary_version": "3.12.3-3build1"
},
{
"binary_name": "cyrus-clients",
"binary_version": "3.12.3-3build1"
},
{
"binary_name": "cyrus-common",
"binary_version": "3.12.3-3build1"
},
{
"binary_name": "cyrus-imapd",
"binary_version": "3.12.3-3build1"
},
{
"binary_name": "cyrus-murder",
"binary_version": "3.12.3-3build1"
},
{
"binary_name": "cyrus-nntpd",
"binary_version": "3.12.3-3build1"
},
{
"binary_name": "cyrus-pop3d",
"binary_version": "3.12.3-3build1"
},
{
"binary_name": "cyrus-replication",
"binary_version": "3.12.3-3build1"
},
{
"binary_name": "libcyrus-imap-perl",
"binary_version": "3.12.3-3build1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "cyrus-imapd",
"purl": "pkg:deb/ubuntu/cyrus-imapd?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
"3.10.2-1",
"3.12.1-2",
"3.12.1-2build1",
"3.12.1-3"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-61911.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "cyrus-admin",
"binary_version": "3.12.1-3"
},
{
"binary_name": "cyrus-caldav",
"binary_version": "3.12.1-3"
},
{
"binary_name": "cyrus-clients",
"binary_version": "3.12.1-3"
},
{
"binary_name": "cyrus-common",
"binary_version": "3.12.1-3"
},
{
"binary_name": "cyrus-imapd",
"binary_version": "3.12.1-3"
},
{
"binary_name": "cyrus-murder",
"binary_version": "3.12.1-3"
},
{
"binary_name": "cyrus-nntpd",
"binary_version": "3.12.1-3"
},
{
"binary_name": "cyrus-pop3d",
"binary_version": "3.12.1-3"
},
{
"binary_name": "cyrus-replication",
"binary_version": "3.12.1-3"
},
{
"binary_name": "libcyrus-imap-perl",
"binary_version": "3.12.1-3"
}
]
}
}
],
"modified": "2026-10-17T12:59:15.920648423Z",
"provider": "osv",
"upstream": [
"CVE-2026-61911"
],
"references": [
"https://ubuntu.com/security/CVE-2026-61911",
"https://www.cve.org/CVERecord?id=CVE-2026-61911"
]
},
"related_cves": [
{
"value": "CVE-2026-61911",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 359568,
"published_at": "2026-09-09T14:00:00+00:00"
}