Arbitrary Argument Injection Affecting dovecot package, versions [,2.4.4)
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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- published20 May 2026
- disclosed12 May 2026
- creditUnknown
Introduced: 12 May 2026
CVE-2026-40020 (opens in a new tab)How to fix?
Upgrade dovecot to version 2.4.4 or higher.
Overview
Affected versions of this package are vulnerable to Arbitrary Argument Injection through the SETACL command in IMAP. An attacker can disrupt normal email service by injecting "anyone" permissions into a user's dovecot-acl file, even when the imap_acl_allow_anyone setting is disabled, which can result in spamming folders to all users and causing service interruption.