Resource exhaustion in Open-Xchange Gmbh Ox Dovecot Pro

CVE-2026-33607

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.

Vulnerability class: DoS (Denial of Service)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.006 (44.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 44.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-33607: held from 0.003 to 0.006.

EPSS over last 30 days · oldest: 0.003 · newest: 0.006 · change: +0.003

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33607?
CVE-2026-33607 is a medium-severity vulnerability in Open-Xchange Gmbh Ox Dovecot Pro, classified under Uncontrolled Resource Consumption. CVSS score: 4.3/10. Published 2026-08-28.
How severe is CVE-2026-33607?
Medium severity. CVSS v3 base score is 4.3 out of 10.