CVE-2026-61909 (GCVE-0-2026-61909)
Vulnerability from cvelistv5 – Published: 2026-09-09 00:00 – Updated: 2026-09-14 15:21
VLAI
EPSS
VEX
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-14 15:17 UTC
CWE
- CWE-420 - Unprotected Alternate Channel
Assigner
References
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| cyrusimap | Cyrus IMAP |
Affected:
0 , < 3.8.8
(semver)
Affected: 3.9.0 , < 3.10.4 (semver) Affected: 3.11.0 , < 3.12.4 (semver) cpe:2.3:a:cyrusimap:cyrus_imap:*:*:*:*:*:*:*:* cpe:2.3:a:cyrusimap:cyrus_imap:*:*:*:*:*:*:*:* cpe:2.3:a:cyrusimap:cyrus_imap:*:*:*:*:*:*:*:* |
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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