CVE-2026-40015
Medium
Description
An attacker that has valid credentials can open many connections to the imap-hibernate service and send invalid commands, which can intermittently cause an out-of-bounds read and crash the process. The crash interrupts hibernated IMAP sessions handled by the affected process, which can cause degradation of service for IMAP. Disable IMAP hibernation. Update to non-vulnerable version. No publicly available exploits are known.
SeverityMedium
CVSS4.3
Exploit probability—
ProductOX Dovecot Pro
PublishedAug 28, 2026
First seenAug 28, 2026
Weakness typeCWE-125Out-of-bounds read
How to fix
Update
- Open-Xchange GmbH OX Dovecot Pro2.3.22.2, 3.0.7, 3.1.6 or later
- Open-Xchange GmbH OX Dovecot CE2.4.5 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Open-Xchange GmbH OX Dovecot Pro | 2.3.0 ≤ v < 2.3.22.2, 3.0.0 ≤ v < 3.0.7, 3.1.0 ≤ v < 3.1.6 | 2.3.22.2, 3.0.7, 3.1.6 |
| Open-Xchange GmbH OX Dovecot CE | 2.3.0 ≤ v < 2.4.5 | 2.4.5 |
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