CVE-2026-109285 open-webui CVE debrief

Who should care

Defenders responsible for Open WebUI deployments, particularly those with knowledge base collaborators, should assess exposure and prioritize verification and remediation. They should review access controls for knowledge base collaborators and monitor for unauthorized file access or deletion. Additionally, defenders should verify and update Open WebUI to version 0.11.4 or later, and track exceptions, retest remediated assets, and close the item only after

Why it matters

CVE-2026-109285 is a low-severity vulnerability in Open WebUI that allows former knowledge base collaborators to access files via stale metadata. Defenders should verify and update Open WebUI, review access controls, and monitor for unauthorized file access or deletion.

• Verification of access controls for knowledge base collaborators is required to prevent unauthorized file access or deletion.
• Defenders must review and update Open WebUI to version 0.11.4 or later to address the vulnerability.
• Monitoring for unauthorized file access or deletion is necessary to detect potential exploitation.

Technical summary

The improper access control vulnerability in Open WebUI allows former knowledge base collaborators to retain access to files via stale cached knowledge base references. This can lead to unauthorized file access or deletion. The vulnerability affects Open WebUI versions 0.6.0 before 0.11.4. Defenders should verify and update Open WebUI to version 0.11.4 or later, review access controls for knowledge base collaborators, and monitor for unauthorized file access or deletion. The CVE record and source item provide details on the improper access control vulnerability in Open WebUI.

Defensive priority

Defenders should prioritize verifying and updating Open WebUI to version 0.11.4 or later, reviewing access controls for knowledge base collaborators, and monitoring for unauthorized file access or deletion.

Recommended defensive actions

• Verify and update Open WebUI to version 0.11.4 or later
• Review access controls for knowledge base collaborators
• Monitor for unauthorized file access or deletion
• 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 improper access control vulnerability in Open WebUI. The vulnerability allows former collaborators to access files via stale metadata. The source item includes references to vendor advisories and a third-party advisory.

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.