CVE-2026-33263 (GCVE-0-2026-33263)
Vulnerability from cvelistv5
Published
2026-08-28 10:12
Modified
2026-08-28 15:55
CWE
  • CWE-403 - Exposure of File Descriptor to Unintended Control Sphere ('File Descriptor Leak')
Summary
When mail_max_userip_connections is set (default 10) and reached, submission-login can crash with epoll() panic caused by file descriptor handling issues. If running in high-security mode (default for community releases), only the new submission connection gets terminated. If running in high-performance mode (default for Pro releases), all connections handled by the submission-login process will be terminated. The crashes can cause failure for user to send a message, or it can cause duplicate messages to be sent. If TLS is not used (in the backend server processing the submission), duplicate deliveries cannot happen, because the crash can only happen at AUTH stage. Limit the number of connections handled by single submission-login process. This has a performance impact though. Update to non-vulnerable version. No publicly available exploits are known.
Impacted products
Vendor Product Version
Open-Xchange GmbH OX Dovecot Pro Version: 2.3.0   
Version: 3.0.0   
Version: 3.1.0   
Create a notification for this product.
Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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