CVE-2026-27855
6.8 · MEDIUMOverview
CVE-2026-27855 is a medium-severity vulnerability affecting dovecot dovecot. It was published on March 27, 2026 and has a CVSS 3.1 base score of 6.8 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 6.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and username is altered in passdb, then OTP credentials can be cached so that same OTP reply is valid. An attacker able to observe an OTP exchange is able to log in as the user. If authentication happens over unsecure connection, switch to SCRAM protocol. Alternatively ensure the communcations are secured, and if possible switch to OAUTH2 or SCRAM. 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, < 2.4.3 | Affected |
| open-xchange | dovecot | 0 | Affected |
Frequently Asked Questions
What is CVE-2026-27855?
CVE-2026-27855 is a medium-severity vulnerability affecting dovecot dovecot. It was published on March 27, 2026 and has a CVSS 3.1 base score of 6.8 (MEDIUM).
How severe is CVE-2026-27855?
This vulnerability has a CVSS 3.1 base score of 6.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-27855?
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-2026-27855?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-27855 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.
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