CVE-2026-40020

CVSS 3.1 LOWEPSS 0.3%CWE-284

Vexday Risk Score

8Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 3.1EPSS 0.3%KEV nãoPoC —Nuclei —Metasploit —Patch referenciado

Lifecycle

12 May 2026Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

Attacker can use the IMAP SETACL command to inject the anyone permission to user's dovecot-acl file even if imap_acl_allow_anyone=no. This causes folders to be spammed to all users. The impact is limited to being able to spam folders to other users, no unexpected access is gained. Install to fixed version. No publicly available exploits are known.

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

Affected products

Open-Xchange GmbH · OX Dovecot Pro

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References

https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0002.json