Use of Expired File Descriptor Affecting dovecot package, versions [2.3.0,2.4.5)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-UNMANAGED-DOVECOT-20078961
- published24 Sept 2026
- disclosed28 Aug 2026
- creditUnknown
Introduced: 28 Aug 2026
CVE-2026-33263 (opens in a new tab)How to fix?
Upgrade dovecot to version 2.4.5 or higher.
Overview
Affected versions of this package are vulnerable to Use of Expired File Descriptor in the submission-login process when the maximum allowed user IP connections is reached, leading to improper file descriptor handling. An attacker can disrupt email sending functionality or cause duplicate message deliveries by exhausting the connection limit and triggering a crash in the affected process.
Workaround
This vulnerability can be mitigated by limiting the number of connections handled by a single submission-login process using the process_limit setting in the configuration.