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CVE-2026-40016

5.3 MEDIUM

Attacker can upload a malicious Sieve script over ManageSieve service (or locally) to bypass configured CPU time limits for Sieve up to 1...

Published: 2026-05-12 · Last updated: 2026-05-18

Severity and scoring

CVSS
5.3 MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE
CWE-400

Affected products

VendorProduct
dovecotdovecot
open-xchangedovecot

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.

Source: NVD

References

Related CVEs

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