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.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:HAttack ComplexityHigh
PR:LPrivileges RequiredLow
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:NIntegrityNone
A:HAvailabilityHigh
Weaknesses
Affected Products
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Impact
References
Timeline
Published
May 12, 2026
Last Updated
May 18, 2026
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