CVE-2026-33603
6.8 · MEDIUMOverview
CVE-2026-33603 is a medium-severity vulnerability affecting dovecot dovecot. It was published on May 12, 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 requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
Technical Description
Attacker can use a specially crafted base64 exchange between Dovecot and Client to fake SCRAM TLS channel binding. This requires that the attacker is able to position itself between Dovecot and the client connection. If successful, the attacker can eavesdrop communications between Dovecot and client as MITM proxy. Install 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-2026-33603?
CVE-2026-33603 is a medium-severity vulnerability affecting dovecot dovecot. It was published on May 12, 2026 and has a CVSS 3.1 base score of 6.8 (MEDIUM).
How severe is CVE-2026-33603?
This vulnerability has a CVSS 3.1 base score of 6.8, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-33603?
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-2026-33603?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-33603 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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