Description
An attacker that has valid credentials can use IMAP LIST command to consume CPU. This can cause degradation or denial of service for IMAP. Monitor system for abnormal CPU usage and kill the offending process and lock account. Alternatively install fixed version. No publicly available exploits are known.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Open-Xchange | OX Dovecot Pro | 2.3.0 – < 3.0.7, 3.1.0 – < 3.1.6 | 3.0.7 |
| Open-Xchange | OX Dovecot CE | 2.3.0 – < 2.4.5 | 2.4.5 |
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 | 1:2.4.5+dfsg1-1 | — |
| Debian 13 | dovecot | 1:2.4.1+dfsg1-6+deb13u7 | — |
| Debian 12 | dovecot | 1:2.3.19.1+dfsg1-2.1+deb12u7 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | dovecot | No fix yet | — |
| Ubuntu 24.04 LTS | dovecot | No fix yet | — |
| Ubuntu 22.04 LTS | dovecot | No fix yet | — |
| 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 | — |
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 |
| SLES 12 SP5 | dovecot22 | 2.2.31-19.40.1 | SUSE-SU-2026:3919-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | dovecot24 | 2.4.4-160000.2.1 | SUSE-SU-2026:23595-1 |
| 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 | 2.4.4-160000.2.1 | SUSE-SU-2026:23595-1 |
| 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 | 2.4.5-1.1 | openSUSE-SU-2026:11629-1 |
| openSUSE Leap 16.0 | dovecot24 | 2.4.4-160000.2.1 | openSUSE-SU-2026:21720-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | dovecot | 2.4.5-r0 | — |
| Alpine v3.23 | dovecot | 2.4.5-r0 | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | dovecot | No fix yet | — |
Advisories 6
- WID-SEC-2026-3076 Dovecot: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- SUSE-SU-2026:23595-1 Security update for dovecot24 SUSE / openSUSE Security Updates · Sep 29, 2026
- SUSE-SU-2026:4139-1 Security update for dovecot23 SUSE / openSUSE Security Updates · Sep 28, 2026
- SUSE-SU-2026:3919-1 Security update for dovecot22 SUSE / openSUSE Security Updates · Sep 10, 2026
- openSUSE-SU-2026:21720-1 Security update for dovecot24 SUSE / openSUSE Security Updates · Sep 2, 2026
- openSUSE-SU-2026:11629-1 dovecot24-2.4.5-1.1 on GA media SUSE / openSUSE Security Updates · Aug 29, 2026