CVE-2026-40013 Affecting dovecot package, versions <1:2.4.5+dfsg1-1


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.46% (38th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-DOVECOT-19424874
  • published29 Aug 2026
  • disclosed28 Aug 2026

Introduced: 28 Aug 2026

NewCVE-2026-40013  (opens in a new tab)

How to fix?

Upgrade Debian:unstable dovecot to version 1:2.4.5+dfsg1-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream dovecot package and not the dovecot package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

An attacker that has valid credentials can submit a Sieve script containing an extreme numeric literal, which causes an out-of-bounds write when the ManageSieve service compiles the script. This causes memory corruption and an observed crash of the ManageSieve process, resulting in denial of service for script management. This might be able to be used for remote code execution. Disable the ManageSieve service if users do not need remote Sieve script management. Update to non-vulnerable version. No publicly available exploits are known.

CVSS Base Scores

version 3.1