CVE-2026-40020
3.1 · LOWOverview
CVE-2026-40020 is a low-severity vulnerability affecting dovecot dovecot. It was published on May 12, 2026 and has a CVSS 3.1 base score of 3.1 (LOW).
This vulnerability has a CVSS 3.1 base score of 3.1, rated LOW. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories and patches from dovecot. Update dovecot to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| dovecot | dovecot | >= 0, < 2.4.4 | Affected |
| open-xchange | dovecot | >= 0, < 3.1.5 | Affected |
Frequently Asked Questions
What is CVE-2026-40020?
CVE-2026-40020 is a low-severity vulnerability affecting dovecot dovecot. It was published on May 12, 2026 and has a CVSS 3.1 base score of 3.1 (LOW).
How severe is CVE-2026-40020?
This vulnerability has a CVSS 3.1 base score of 3.1, rated LOW. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-40020?
Check the references section for vendor advisories and patches from dovecot. Update dovecot to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-40020?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-40020 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
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Browser-based exploitation validates findings with real proof-of-concept.
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