Vulnerability in Cyrus Imap
CVE-2026-61909
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.5 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.002 (9.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 10th percentile — 9.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
Weakness classification (CWE)
References
- cyrusimap.org (Product)
- www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.4.html (Release Notes)
- www.cyrusimap.org/3.12/imap/download/release-notes/3.10/x/3.10.4.html (Release Notes)
- www.cyrusimap.org/3.12/imap/download/release-notes/3.8/x/3.8.8.html (Release Notes)
Frequently asked questions
- What is CVE-2026-61909?
- CVE-2026-61909 is a low-severity vulnerability in Cyrus Imap, classified under Unprotected Alternate Channel. CVSS score: 3.5/10. Published 2026-09-09.
- How severe is CVE-2026-61909?
- Low severity. CVSS v3 base score is 3.5 out of 10.