CVE-2026-109296 open-webui CVE debrief

Who should care

Defenders responsible for Open WebUI deployments should assess exposure and prioritize verification and remediation efforts to prevent potential security breaches. This includes reviewing compensating controls for exposed systems, checking relevant monitoring and logs, and tracking exceptions and retesting remediated assets. Security teams and vulnerability management teams should also review the vulnerability and plan vendor-supported updates or mitigates

Why it matters

The missing authorization vulnerability in Open WebUI before 0.11.4 allows authenticated users to reach disabled model provider backends, potentially leading to unauthorized access.

• Authenticated users can reach disabled model provider backends
• Potential for unauthorized access to sensitive model provider backends
• Need to verify and upgrade to Open WebUI version 0.11.4 or later

Technical summary

The vulnerability allows authenticated users to reach disabled model provider backends by supplying an explicit backend index on Ollama and OpenAI-compatible listing routes. This can potentially lead to unauthorized access to sensitive model provider backends. The affected product is Open WebUI before version 0.11.4, and defenders should prioritize verifying and upgrading to the latest version to prevent exploitation. The vulnerability is rated as MEDIUM with a CVSS score of 5.3, and defenders should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.

Defensive priority

Defenders should prioritize verifying and upgrading to Open WebUI version 0.11.4 or later, and restrict access to sensitive model provider backends.

Recommended defensive actions

• Verify and upgrade to Open WebUI version 0.11.4 or later
• Restrict access to sensitive model provider backends
• Monitor for suspicious activity on model provider backends
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and source item provide details on the missing authorization vulnerability in Open WebUI before 0.11.4. The vulnerability allows authenticated users to reach disabled model provider backends by supplying an explicit backend index. Evidence is limited to the information provided in the CVE record and source item, and defenders should verify the affected scope and severity through official advisories or CVE records.

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.