Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-61909

CVE-2026-61909MEDIUM

cyrusimap Cyrus IMAP — An issue was discovered in Cyrus IMAP before 3.12.4.

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   L   N  U  L  N  N    4.3   .0020    9.4     —

AFFECTED
  Product     Versions     Fixed
  Cyrus IMAP  unspecified  —

TIMELINE
  Jul 13  Reserved by mitre
  Sep 9   Published (CNA: mitre)
  Sep 16  RESCORED — CVE-2026-61909 (cyrusimap Cyrus IMAP). CVSS 3.5 → 4.3 (NVD).

CWE-420 · CNA: mitre · CVSS v3.1 · 4 references · NVD status: Analyzed

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
July 13, 2026	Reserved	Reserved by mitre
September 9, 2026	Published	Published (CNA: mitre)
September 16, 2026	RESCORED	RESCORED — CVE-2026-61909 (cyrusimap Cyrus IMAP). CVSS 3.5 → 4.3 (NVD).

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
cyrusimap	Cyrus IMAP	—	—	—

Weaknesses

CWE-420

References (4)

https://cyrusimap.org [Product]
https://www.cyrusimap.org/3.12/imap/download/release-notes/3.10/x/3.10.4.html [Release Notes]
https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.4.html [Release Notes]
https://www.cyrusimap.org/3.12/imap/download/release-notes/3.8/x/3.8.8.html [Release Notes]

Authoritative record: CVE-2026-61909 at cve.org

Vendors: cyrusimap

Weaknesses: CWE-420

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-61909 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.