CVE-2026-40016
Undergoing Analysis Undergoing Analysis - In Progress
BaseFortify

Publication date: 2026-05-12

Last updated on: 2026-05-18

Assigner: Open-Xchange

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.
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Meta Information
Published
2026-05-12
Last Modified
2026-05-18
Generated
2026-06-10
EPSS Evaluated
2026-06-08
NVD
Affected Vendors & Products
Showing 2 associated CPEs
Vendor Product Version / Range
dovecot dovecot to 2.4.4 (exc)
open-xchange dovecot to 3.1.5 (exc)
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Exploitability
CWE
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KEV
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CWE ID Description
CWE-400 The product does not properly control the allocation and maintenance of a limited resource.
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