Description
Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory.
Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install fixed version. No publicly available exploits are known.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Open-Xchange | OX Dovecot Pro | ≤ 2.3.0, ≤ 3.1.0, ≤ 2.4.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | dovecot | 1:2.4.3+dfsg1-1 | — |
| Debian 13 | dovecot | 1:2.4.1+dfsg1-6+deb13u4 | — |
| Debian 12 | dovecot | 1:2.3.19.1+dfsg1-2.1+deb12u2 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 25.10 | dovecot | 1:2.4.1+dfsg1-5ubuntu4.1 | — |
| Ubuntu 24.04 LTS | dovecot | 1:2.3.21+dfsg1-2ubuntu6.3 | — |
| Ubuntu 22.04 LTS | dovecot | 1:2.3.16+dfsg1-3ubuntu2.7 | — |
| Ubuntu 20.04 LTS | dovecot | No fix yet | — |
| Ubuntu 18.04 LTS | dovecot | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | dovecot | No fix yet | — |
| Ubuntu Pro 14.04 LTS | dovecot | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | dovecot +4 | 1:2.3.21-16.el10_1.1 | RHSA-2026:19149, RHSA-2026:13498 |
| RHEL 9 | dovecot +4 | 1:2.3.16-15.el9_7.1 | RHSA-2026:19364, RHSA-2026:13857 |
| RHEL 8 | dovecot +4 | 1:2.3.16-7.el8_10 | RHSA-2026:13830 |
Show 13 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10.0 EUS | dovecot +4 | 1:2.3.21-16.el10_0.1 | RHSA-2026:17602 |
| RHEL 9.6 EUS | dovecot +4 | 1:2.3.16-15.el9_6.1 | RHSA-2026:17626 |
| RHEL 9.4 EUS | dovecot +4 | 1:2.3.16-11.el9_4.2 | RHSA-2026:17625 |
| RHEL 9.2 E4S | dovecot +3 | 1:2.3.16-8.el9_2.2 | RHSA-2026:17628 |
| RHEL 9.0 E4S | dovecot +3 | 1:2.3.16-3.el9_0.1 | RHSA-2026:17630 |
| RHEL 8.8 TUS | dovecot +3 | 1:2.3.16-3.el8_8.1 | RHSA-2026:18053 |
| RHEL 8.8 E4S | dovecot +3 | 1:2.3.16-3.el8_8.1 | RHSA-2026:18053 |
| RHEL 8.6 TUS | dovecot +3 | 1:2.3.16-2.el8_6.1 | RHSA-2026:19453 |
| RHEL 8.6 E4S | dovecot +3 | 1:2.3.16-2.el8_6.1 | RHSA-2026:19453 |
| RHEL 8.6 AUS | dovecot +3 | 1:2.3.16-2.el8_6.1 | RHSA-2026:19453 |
| RHEL 8.4 EUS Long Life | dovecot +3 | 1:2.3.8-9.el8_4.1 | RHSA-2026:19455 |
| RHEL 8.4 AUS | dovecot +3 | 1:2.3.8-9.el8_4.1 | RHSA-2026:19455 |
| RHEL 7 ELS | dovecot +4 | 1:2.2.36-8.el7_9.1 | RHSA-2026:26564 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | dovecot +4 | 1:2.3.21-16.el10_1.1 | ALSA-2026:19149, ALSA-2026:13498 |
| AlmaLinux 9 | dovecot +4 | 1:2.3.16-15.el9_7.1 | ALSA-2026:19364, ALSA-2026:13857 |
| AlmaLinux 8 | dovecot +4 | 1:2.3.16-7.el8_10 | ALSA-2026:13830 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | dovecot | 1:2.3.21-16.el10_1.1 | RLSA-2026:19149, RLSA-2026:13498 |
| Rocky Linux 9 | dovecot | 1:2.3.16-15.el9_7.1 | RLSA-2026:19364, RLSA-2026:13857 |
| Rocky Linux 8 | dovecot | 1:2.3.16-7.el8_10 | RLSA-2026:13830 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | dovecot23 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 |
| SLES 15 SP6 | dovecot23 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 |
| SLES 15 SP5 | dovecot23 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 |
| SLES 15 SP4 | dovecot23 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | dovecot24 | 2.4.3-160000.1.1 | SUSE-SU-2026:21208-1 |
| SLES for SAP 15 SP6 | dovecot23 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 |
| SLES for SAP 15 SP5 | dovecot23 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 |
| SLES for SAP 15 SP4 | dovecot23 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 |
| SLES 16.0 | dovecot24 | 2.4.3-160000.1.1 | SUSE-SU-2026:21208-1 |
| SLE HPC 15 SP5 | dovecot23 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 |
| SLE HPC 15 SP4 | dovecot23 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | dovecot24 | 2.4.3-1.1 | openSUSE-SU-2026:10442-1 |
| openSUSE Leap 16.0 | dovecot24 | 2.4.3-160000.1.1 | openSUSE-SU-2026:20554-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | dovecot +4 | 1:2.3.20-1.amzn2023.0.3 | ALAS2023-2026-1570 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | dovecot | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | dovecot +4 | 1:2.3.21-16.el10_1.1 | ELSA-2026-19149, ELSA-2026-13498 |
| Oracle Linux 9 | dovecot +4 | 1:2.3.16-15.el9_7.1 | ELSA-2026-19364, ELSA-2026-13857 |
| Oracle Linux 8 | dovecot +4 | 1:2.3.16-7.el8_10 | ELSA-2026-13830 |
| Oracle Linux 7 | dovecot +4 | 1:2.2.36-8.el7 | ELSA-2026-26564 |
Advisories 36
- ALSA-2026:13498 Important: dovecot security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:19364 Important: dovecot security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:13857 Important: dovecot security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:19149 Important: dovecot security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:13830 Important: dovecot security update AlmaLinux Security Advisories · Oct 29, 2026
- SUSE-SU-2026:4139-1 Security update for dovecot23 SUSE / openSUSE Security Updates · Sep 28, 2026
- WID-SEC-2026-0891 Dovecot: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 16, 2026
- ELSA-2026-26564 Important: dovecot security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Aug 10, 2026
- ELSA-2026-19149 Important: dovecot security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Jul 16, 2026
- RHSA-2026:26564 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:19455 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:19453 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:19364 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:19149 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:18053 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:17628 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:17630 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:17625 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:17626 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:17602 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:13857 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:13830 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:13498 Red Hat Security Advisory: dovecot security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- ELSA-2026-19364 Important: dovecot security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jun 23, 2026
- RLSA-2026:19149 Important: dovecot security update Rocky Linux Security Advisories · May 29, 2026
- RLSA-2026:19364 Important: dovecot security update Rocky Linux Security Advisories · May 28, 2026
- RLSA-2026:13857 Important: dovecot security update Rocky Linux Security Advisories · May 7, 2026
- RLSA-2026:13830 Important: dovecot security update Rocky Linux Security Advisories · May 7, 2026
- RLSA-2026:13498 Important: dovecot security update Rocky Linux Security Advisories · May 6, 2026
- ELSA-2026-13857 Important: dovecot security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · May 6, 2026
- ELSA-2026-13830 Important: dovecot security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 6, 2026
- ELSA-2026-13498 Important: dovecot security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · May 5, 2026
- openSUSE-SU-2026:20554-1 Security update for dovecot24 SUSE / openSUSE Security Updates · Apr 22, 2026
- SUSE-SU-2026:21208-1 Security update for dovecot24 SUSE / openSUSE Security Updates · Apr 22, 2026
- ALAS2023-2026-1570 Important: dovecot security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Apr 13, 2026
- openSUSE-SU-2026:10442-1 dovecot24-2.4.3-1.1 on GA media SUSE / openSUSE Security Updates · Mar 28, 2026