CVE-2026-90800 Apache Software Foundation CVE debrief

Who should care

Defenders and administrators of Apache CouchDB instances should assess exposure and prioritize upgrading to version 3.5.3. They should review compensating controls for exposed systems, verify affected scope and severity, and monitor for unauthorized access to CouchDB databases. Security teams and vulnerability management teams should also be aware of the potential impact and take necessary actions to prevent data exposure.

Why it matters

The authentication bypass vulnerability in Apache CouchDB 3.5.2 and below requires immediate attention from defenders and administrators to prevent potential data exposure.

• Potential unauthorized access to sensitive data in prefixed _users and _replicator databases
• Need to verify and update access controls for these databases
• Possible data exposure requires review and remediation

Technical summary

The vulnerability allows unauthorized access to read the full contents of prefixed _users and _replicator databases in Apache CouchDB 3.5.2 and below. This is caused by missing authorization checks in chttpd, which enables an attacker to access sensitive data without proper authentication. The issue requires immediate attention from defenders and administrators to prevent potential data exposure. Affected product deployments should prioritize upgrading to version 3.5.3 to fix the authentication bypass vulnerability.

Defensive priority

Upgrade to version 3.5.3 to fix the authentication bypass vulnerability.

Recommended defensive actions

• Upgrade to Apache CouchDB version 3.5.3
• Review and update access controls for prefixed _users and _replicator databases
• Monitor for unauthorized access to CouchDB databases
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record and source item provide details on the authentication bypass vulnerability in Apache CouchDB 3.5.2 and below. The issue is caused by missing authorization checks in chttpd, allowing unauthorized access to prefixed _users and _replicator databases. Defenders should verify the affected scope and severity, and review compensating controls for exposed systems. The source confidence is high, but the exact impact and affected deployments are not specified.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.