CVE-2026-40020
mediumpriority · track · 17EPSS 0.003 · 18 %ileDEEURUUSEPSS · scored 2026-10-27
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.1–4.3
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (26)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-1510OX Dovecot Pro: Mehrere SchwachstellenDeutsch2026-05-12csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in OX Dovecot Pro ausnutzen, um SQL-Injection-Angriffe durchzuführen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren oder offenzulegen oder einen Denial-of-Service-Zustand zu verursachen.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (4)
External citations — patches, advisories, analysis.
- https://documentation.open-xchange.com/dovecot/security/advisories/html/2026/oxdc-adv-2026-0002.html#cve-2026-40020-imap-folders-can-be-shared-spammed-to-everyonePatchcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2026-40020cnnvd
- https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0002.jsonenisa_euvd
- https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0002.jsonVendor Advisorynvd
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