Vulnerability · Published Sep 9, 2026 · Assigned by mitre
CVE-2026-61907
Medium 4.3
In plain English
A medium-severity incorrect authorization in Cyrus IMAP from cyrusimap. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 12% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
An issue was discovered in Cyrus IMAP before 3.12.4. JMAP snooze bypasses the destination-mailbox ACL. An authenticated user with insert permissions on another user's snoozed mailbox could cause insertion of mail to that user's inbox, or any other of their mailboxes whose id was known to the user, despite having no insert permissions to the target mailbox.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | cyrus-imapd | no fix listed | DEBIAN-CVE-2026-61907 |
| Debian:13 | cyrus-imapd | no fix listed | DEBIAN-CVE-2026-61907 |
| Debian:14 | cyrus-imapd | 3.12.4-1 | DEBIAN-CVE-2026-61907 |
| Ubuntu:26.04:LTS | cyrus-imapd | no fix listed | UBUNTU-CVE-2026-61907 |
| Ubuntu:26.10 | cyrus-imapd | no fix listed | UBUNTU-CVE-2026-61907 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| cyrusimap | Cyrus IMAP | 0 – before 3.8.83.9.0 – before 3.10.43.11.0 – before 3.12.4 |
Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N