Vulnerability · Published Sep 9, 2026 · Assigned by mitre
CVE-2026-61915
Medium 4.2
In plain English
A medium-severity double free 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 0.3% (higher than 18% 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. There is a VPATCH BYPARAM double-free. An authenticated calendar user could crash a Cyrus CalDAV worker with a PATCH containing PATCH-ACTION="BYPARAM@..." against a resource with two or more properties of the matched kind. The memory holding the selector would be freed once on each iteration over the properties.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | cyrus-imapd | no fix listed | DEBIAN-CVE-2026-61915 |
| Debian:13 | cyrus-imapd | no fix listed | DEBIAN-CVE-2026-61915 |
| Debian:14 | cyrus-imapd | 3.12.4-1 | DEBIAN-CVE-2026-61915 |
| Ubuntu:26.04:LTS | cyrus-imapd | no fix listed | UBUNTU-CVE-2026-61915 |
| Ubuntu:26.10 | cyrus-imapd | no fix listed | UBUNTU-CVE-2026-61915 |
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-415 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L