Auth bypass in Cyrusimap Cyrus Imap

CVE-2026-47082

An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. The vacation "fcc" feature skips the destination-mailbox ACL. A user whose vacation Sieve script used :fcc (to save a copy of the sent message) could deliver vacation auto-reply copies into any mailbox the script could name, regardless of whether the script owner had insert permissions on the destination mailbox.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L.

EPSS exploit prediction

EPSS: 0.003 (21.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 21.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-47082: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-47082?
CVE-2026-47082 is a medium-severity vulnerability in Cyrusimap Cyrus Imap, classified under Incorrect Authorization. CVSS score: 5.4/10. Published 2026-07-16.
How severe is CVE-2026-47082?
Medium severity. CVSS v3 base score is 5.4 out of 10.