CVE-2026-40019

MEDIUM
5.9
CVSS Score
Published: August 28, 2026 at 10:12 AM UTC
Updated: September 3, 2026 at 06:24 PM UTC
1 product affected across 1 vendorOX Dovecot

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Severity
MEDIUM5.9
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

Description

An unauthenticated attacker can send a truncated quoted argument to the ManageSieve login process, which makes it spin in an infinite loop consuming CPU. This can cause degradation or denial of service for Sieve script management, and repeated connections can consume all available CPU on the server. Monitor system for abnormal CPU usage and kill the offending process. Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

2.4.3 ≤ v < 2.4.52.4.3
Affected range stops below 2.4.5, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.9MEDIUMOX
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-400

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