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5.3Medium

CVE-2026-40016

Open-Xchange GmbH OX Dovecot Pro Published: (6 months ago)

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.

Weakness (CWE): CWE-400

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

VendorProductVersions
dovecot dovecot < 2.4.4
open-xchange dovecot < 3.1.5
Open-Xchange GmbH OX Dovecot Pro ≤ 2.3.0

References and patches

CPE matches (NVD) (2)
  • cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:* < 2.4.4
  • cpe:2.3:a:open-xchange:dovecot:*:*:*:*:pro:*:*:* < 3.1.5

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