Infinite loop Affecting dovecot package, versions [2.4.3,2.4.5)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.37% (29th percentile)

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  • Snyk IDSNYK-UNMANAGED-DOVECOT-20078959
  • published24 Sept 2026
  • disclosed28 Aug 2026
  • creditUnknown

Introduced: 28 Aug 2026

CVE-2026-40019  (opens in a new tab)
CWE-835  (opens in a new tab)

How to fix?

Upgrade dovecot to version 2.4.5 or higher.

Overview

Affected versions of this package are vulnerable to Infinite loop via the ManageSieve login process. An attacker can cause the process to enter an infinite loop and exhaust CPU resources by sending a specially crafted, truncated quoted argument. This can lead to service degradation or complete unavailability by repeatedly making such connections.

Workaround

This vulnerability can be mitigated by restricting network access to the ManageSieve service to trusted clients only, such as by configuring a firewall to limit incoming connections to the service port from authorized IP addresses or subnets.

CVSS Base Scores

version 4.0
version 3.1