CVE-2026-40016
Fixed in a distro release EPSS <1%CVSS 5.3
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.
Products: Open-Xchange GmbH OX Dovecot Pro
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Alpine 3.23 | dovecot | 2.4.4-r0 |
| Alpine 3.24 | dovecot | 2.4.4-r0 |
| Debian 12 | dovecot | 1:2.3.19.1+dfsg1-2.1+deb12u6 |
| Debian 13 | dovecot | 1:2.4.1+dfsg1-6+deb13u6 |
| Debian 14 | dovecot | 1:2.4.4+dfsg1-1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server 16.0 | dovecot24 | 2.4.4-160000.1.1 |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | dovecot22 | 2.2.31-19.43.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | dovecot24 | 2.4.4-160000.1.1 |
| Ubuntu 16.04 LTS | dovecot | no fix |
| Ubuntu 18.04 LTS | dovecot | no fix |
| Ubuntu 20.04 LTS | dovecot | no fix |
| Ubuntu 22.04 LTS | dovecot | 1:2.3.16+dfsg1-3ubuntu2.9 |
| Ubuntu 24.04 LTS | dovecot | 1:2.3.21+dfsg1-2ubuntu6.5 |
| Ubuntu 25.10 | dovecot | 1:2.4.1+dfsg1-5ubuntu4.2 |
| Ubuntu 26.04 LTS | dovecot | 1:2.4.2+dfsg1-3ubuntu2.1 |
| Ubuntu Pro 14.04 LTS | dovecot | no fix |
| openSUSE Leap 16.0 | dovecot24 | 2.4.4-160000.1.1 |
| openSUSE Tumbleweed | dovecot24 | 2.4.4-1.1 |