CVE-2026-33605
Fixed in a distro release EPSS <1%CVSS 7.5
An unauthenticated attacker can crash the ManageSieve login process by sending a small malformed command before authenticating. If running in high-security mode (default for community releases), only the attacker's own connection is terminated. If running in high-performance mode (default for Pro releases), all connections handled by the same managesieve-login process are terminated. Repeating the attack can cause denial of service for Sieve script management. Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known.
Products: Open-Xchange GmbH OX Dovecot Pro, Open-Xchange GmbH OX Dovecot CE
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| AlmaLinux 10 | dovecot | 1:2.3.21-19.el10_2.8 |
| AlmaLinux 10 | dovecot-devel | 1:2.3.21-19.el10_2.8 |
| AlmaLinux 10 | dovecot-mysql | 1:2.3.21-19.el10_2.8 |
| AlmaLinux 10 | dovecot-pgsql | 1:2.3.21-19.el10_2.8 |
| AlmaLinux 10 | dovecot-pigeonhole | 1:2.3.21-19.el10_2.8 |
| AlmaLinux 8 | dovecot | 1:2.3.16-16.el8_10 |
| AlmaLinux 8 | dovecot-devel | 1:2.3.16-16.el8_10 |
| AlmaLinux 8 | dovecot-mysql | 1:2.3.16-16.el8_10 |
| AlmaLinux 8 | dovecot-pgsql | 1:2.3.16-16.el8_10 |
| AlmaLinux 8 | dovecot-pigeonhole | 1:2.3.16-16.el8_10 |
| AlmaLinux 9 | dovecot | 1:2.3.16-18.el9_8.8 |
| AlmaLinux 9 | dovecot-devel | 1:2.3.16-18.el9_8.8 |
| AlmaLinux 9 | dovecot-mysql | 1:2.3.16-18.el9_8.8 |
| AlmaLinux 9 | dovecot-pgsql | 1:2.3.16-18.el9_8.8 |
| AlmaLinux 9 | dovecot-pigeonhole | 1:2.3.16-18.el9_8.8 |
| Alpine 3.23 | dovecot | 2.4.5-r0 |
| Alpine 3.24 | dovecot | 2.4.5-r0 |
| Debian 12 | dovecot | no fix |
| Debian 13 | dovecot | 1:2.4.1+dfsg1-6+deb13u7 |
| Debian 14 | dovecot | 1:2.4.5+dfsg1-1 |
| Red Hat Enterprise Linux 10.2 | dovecot | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 10.2 | dovecot-debuginfo | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 10.2 | dovecot-debugsource | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 10.2 | dovecot-devel | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 10.2 | dovecot-mysql | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 10.2 | dovecot-mysql-debuginfo | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 10.2 | dovecot-pgsql | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 10.2 | dovecot-pgsql-debuginfo | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 10.2 | dovecot-pigeonhole | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 10.2 | dovecot-pigeonhole-debuginfo | 1:2.3.21-19.el10_2.8 |
| Red Hat Enterprise Linux 8 | dovecot | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-debuginfo | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-debugsource | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-devel | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-mysql | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-mysql-debuginfo | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-pgsql | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-pgsql-debuginfo | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-pigeonhole | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-pigeonhole-debuginfo | 1:2.3.16-16.el8_10 |
| Red Hat Enterprise Linux 9 | dovecot | 1:2.3.16-18.el9_8.8 |
| Red Hat Enterprise Linux 9 | dovecot-debuginfo | 1:2.3.16-18.el9_8.8 |
| Red Hat Enterprise Linux 9 | dovecot-debugsource | 1:2.3.16-18.el9_8.8 |
| Red Hat Enterprise Linux 9 | dovecot-devel | 1:2.3.16-18.el9_8.8 |
| Red Hat Enterprise Linux 9 | dovecot-mysql | 1:2.3.16-18.el9_8.8 |
| Red Hat Enterprise Linux 9 | dovecot-mysql-debuginfo | 1:2.3.16-18.el9_8.8 |
| Red Hat Enterprise Linux 9 | dovecot-pgsql | 1:2.3.16-18.el9_8.8 |
| Red Hat Enterprise Linux 9 | dovecot-pgsql-debuginfo | 1:2.3.16-18.el9_8.8 |
| Red Hat Enterprise Linux 9 | dovecot-pigeonhole | 1:2.3.16-18.el9_8.8 |
| Red Hat Enterprise Linux 9 | dovecot-pigeonhole-debuginfo | 1:2.3.16-18.el9_8.8 |
| Rocky Linux 10 | dovecot | 1:2.3.21-19.el10_2.8 |
| Rocky Linux 8 | dovecot | 1:2.3.16-16.el8_10 |
| Rocky Linux 9 | dovecot | 1:2.3.16-18.el9_8.8 |
| 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 12 SP5-LTSS | dovecot22 | 2.2.31-19.40.1 |
| 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 | 2.4.4-160000.2.1 |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | dovecot22 | 2.2.31-19.40.1 |
| 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 | 2.4.4-160000.2.1 |
| 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 | no fix |
| Ubuntu 24.04 LTS | dovecot | no fix |
| Ubuntu 26.04 LTS | dovecot | no fix |
| Ubuntu Pro 14.04 LTS | dovecot | no fix |
| openSUSE Leap 16.0 | dovecot24 | 2.4.4-160000.2.1 |
| openSUSE Tumbleweed | dovecot24 | 2.4.5-1.1 |