🛡️ CVE-2026-40016
🟡 CVSS 5.3 — Medium ✅ No Known Exploit CWE-400 NVD
5.3
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Attacker can upload a malicious Sieve script over ManageSieve service (or locally) to bypass configured CPU time limits for Sieve up to 130 times of the configured limit. Attacker can use this to degrade server performance and bypass configured CPU time limits for Sieve scripts. Install fixed version, or alternatively prevent direct access to Sieve scripts via ManageSieve or local access. No publicly available exploits are known.

Details

Severity MEDIUM
CVSS Score 5.3
CVSS Vector CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE CWE-400
Public Exploit ✅ No
Source NVD
Published 2026-05-12
Updated 2026-06-02
Modified 2026-05-18
Fix URL N/A

Affected Packages

Software From version Fixed in
dovecot 3.1.5
unknown

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