CVE-2026-40016
CVE-2026-40016
Vexday Risk Score
13Low
SSVC decision (CISA)
Track
No exploitation signal → monitor
CVSS 5.3EPSS 0.3%KEV nãoPoC —Nuclei —Metasploit —Patch referenciado
Lifecycle
12 May 2026Published on NVD
Recommendation: Monitor — no exploitation signal at the moment.
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.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected products
Open-Xchange GmbH · OX Dovecot ProWant to know if your infrastructure is exposed to this?
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