CVE-2026-61915: cyrus imap Double Free
Vulnerability summary
CVE-2026-61915 is a high (CVSS 7.1) Double Free vulnerability in cyrus imap. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 16.4% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 09-09-2026PublishedVulnerability first disclosed.
- 10-09-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
4 scores · 4 sources · 1 version- CVE.orgCNA4.2MediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:LDiffers
- OSV · UbuntuEcosystem advisory · calculated7.1HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H
- OSV · DebianEcosystem advisory · calculated7.1HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H
EPSS trend
Probability
0.26%
Chance of exploitation in the next 30 days
Percentile
16%
Versus all other CVEs
30-day change
0.00 pp
From 0.26% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Cyrus1 product
- imap< 3.8.8 | ≥ 3.9.0, < 3.10.4 | ≥ 3.11.0, < 3.12.4
Cyrusimap1 product
- cyrus_imap< 3.8.8 | ≥ 3.9.0, < 3.10.4 | ≥ 3.11.0, < 3.12.4
Debian1 product
- cyrus-imapdAll versions (No fix recorded) | < 3.12.4-1
Ubuntu1 product
- cyrus-imapdAll versions (No fix recorded)
4 vendors · 4 products
References
7 links- cyrusimap.orgProduct