# CVE-2026-33607: dovecot: An attacker that has valid credentials can use IMAP LIST command to consume CPU

CVE-2026-33607 is fixed in 12 products on 1 platform, first by SUSE-SU-2026:23595-1, released September 1, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-33607
- Priority: Routine
- CVSS: 4.3 (medium)
- EPSS: 0.0055
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 28, 2026

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | dovecot Debian 12.15 (bookworm) | 1:2.3.19.1+dfsg1-2.1+deb12u7 | [DEBIAN-CVE-2026-33607](https://patchblox.com/security/data/fix/linux/debian-cve-2026-33607.md) | Sep 10, 2026 |
| Linux | dovecot Debian 13.5 (trixie) | 1:2.4.1+dfsg1-6+deb13u7 | [DEBIAN-CVE-2026-33607](https://patchblox.com/security/data/fix/linux/debian-cve-2026-33607.md) | Sep 10, 2026 |
| Linux | dovecot Debian 14 | 1:2.4.5+dfsg1-1 | [DEBIAN-CVE-2026-33607](https://patchblox.com/security/data/fix/linux/debian-cve-2026-33607.md) | Sep 10, 2026 |
| Linux | dovecot Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot-debuginfo Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot-debugsource Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot-devel Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot-mysql Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot-mysql-debuginfo Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot-pgsql Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot-pgsql-debuginfo Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot-pigeonhole Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot-pigeonhole-debuginfo Fedora 43 | 1:2.4.5-1.fc43 | [FEDORA-2026-E8A6485109](https://patchblox.com/security/data/fix/linux/fedora-2026-e8a6485109.md) | Sep 10, 2026 |
| Linux | dovecot23 sles 15.6 | 2.3.21.1-150200.76.1 | [SUSE-SU-2026:4139-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4139-1.md) | Sep 14, 2026 |
| Linux | dovecot23 sles 15.7 | 2.3.21.1-150200.76.1 | [SUSE-SU-2026:4139-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4139-1.md) | Sep 14, 2026 |
| Linux | dovecot24 opensuse-leap 16.0 | 2.4.4-160000.2.1 | [OPENSUSE-SU-2026:21720-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21720-1.md) | Sep 1, 2026 |
| Linux | dovecot24 sles 16.0 | 2.4.4-160000.2.1 | [SUSE-SU-2026:23595-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-23595-1.md) | Sep 1, 2026 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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