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 Sep 9, 2026
  • CVSS 4.3 medium
  • 0.2% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-61909 at the National Vulnerability Database