Description
A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU. A suitably formatted mail message causes mail delivery process to consume large amounts of CPU time. Use MTA capabilities to limit RFC 2231 MIME parameters in mail messages, or upgrade to fixed version where the processing is limited. No publicly available exploits are known.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Open-Xchange | OX Dovecot Pro | ≤ 3.0.2, ≤ 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 | — |
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 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | dovecot | 2.4.3-r0 | — |
| Alpine v3.23 | dovecot | 2.4.3-r0 | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | dovecot | No fix yet | — |
Advisories 5
- 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
- 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
- openSUSE-SU-2026:10442-1 dovecot24-2.4.3-1.1 on GA media SUSE / openSUSE Security Updates · Mar 28, 2026