CVE-2026-61909CWE-420

CVE-2026-61909

Low · published September 10, 2026

CVSS v3.1

3.5

EPSS

Percentile

9.9

In the wild

Unconfirmed

What it is

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.

The record

Technical detail

CVSS v3.1: 3.5 · LOW
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N
CVSS v4.0: Not supplied
EPSS: 0.00204 · 9.9th percentile
Weakness: CWE-420 · Unprotected Alternate Channel
Published: 2026-09-10T00:18Z

Affected products (3)

Product	Versions	Fixed in
cyrus/imap	< 3.8.8	3.8.8
cyrus/imap	≥ 3.9.0, < 3.10.4	3.10.4
cyrus/imap	≥ 3.11.0, < 3.12.4	3.12.4

References (4)

https://cyrusimap.org · [email protected]https://www.cyrusimap.org/3.12/imap/download/release-notes/3.10/x/3.10.4.html · [email protected]https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.4.html · [email protected]https://www.cyrusimap.org/3.12/imap/download/release-notes/3.8/x/3.8.8.html · [email protected]

EPSS history

Timeline

11 SEP 03:18Z
EPSS moved — → 0%
epss
09 SEP 00:00Z
An issue was discovered in Cyrus IMAP before 3.12.4
cvelistv5