CVE-2026-61909

cyrus-imapd: cyrus-imapd: CalDAV/CardDAV multiget bypasses per-href ACL

Published Sep 9, 2026 CVSS 3.1 · 3.5 Low EPSS < 1% KEV · Not listed
Description
An issue was discovered in Cyrus IMAP before 3.12.4. CalDAV/CardDAV multiget bypasses a per-href ACL. An authenticated DAV user with some shared access to another user's calendar or address book could read even unshared events or contacts by including the target hrefs in a calendar-multiget or addressbook-multiget REPORT.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Cyrus
Cyrus imap
CPEs cpe:2.3:a:cyrus:imap:*:*:*:*:*:*:*:*
Vendors & Products Cyrus
Cyrus imap
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title CalDAV/CardDAV Multiget ACL Bypass in Cyrus IMAP cyrus-imapd: cyrus-imapd: CalDAV/CardDAV multiget bypasses per-href ACL
References
Metrics threat_severity

None

threat_severity

Moderate

Type Values Removed Values Added
Title CalDAV/CardDAV Multiget ACL Bypass in Cyrus IMAP
Type Values Removed Values Added
Description An issue was discovered in Cyrus IMAP before 3.12.4. CalDAV/CardDAV multiget bypasses a per-href ACL. An authenticated DAV user with some shared access to another user's calendar or address book could read even unshared events or contacts by including the target hrefs in a calendar-multiget or addressbook-multiget REPORT.
First Time appeared Cyrusimap
Cyrusimap cyrus Imap
Weaknesses CWE-420
CPEs cpe:2.3:a:cyrusimap:cyrus_imap:*:*:*:*:*:*:*:*
Vendors & Products Cyrusimap
Cyrusimap cyrus Imap
References
Metrics cvssV3_1

{'score': 3.5, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Sep 14, 2026, 3:21 PM
Reserved
Jul 13, 2026, 12:00 AM
Status
Analyzed
Published
Sep 9, 2026, 8:18 PM
Modified
Sep 16, 2026, 3:24 PM
Severity
Moderate
Public date
Sep 10, 2026, 7:42 AM