Resource exhaustion in Open-Xchange Gmbh Ox Dovecot Ce
CVE-2026-52687
An attacker that has valid credentials can select a compression algorithm for the IMAP connection whose decompression state requires a large amount of memory, and open several such connections. The memory limit of the process is reached with only a few connections, terminating the process and all connections it handles, which can cause degradation or denial of service for IMAP. Disable IMAP compression. Alternatively limit the number of connections handled by a single imap-login process, though this has a performance impact. Update to non-vulnerable version. No publicly available exploits are known.
Vulnerability class: DoS (Denial of Service)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (32.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 32.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001
Affected products
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-52687?
- CVE-2026-52687 is a medium-severity vulnerability in Open-Xchange Gmbh Ox Dovecot Ce, classified under Uncontrolled Resource Consumption. CVSS score: 6.5/10. Published 2026-08-28.
- How severe is CVE-2026-52687?
- Medium severity. CVSS v3 base score is 6.5 out of 10.