CVE-2026-88000 open-webui CVE debrief

Who should care

Defenders responsible for Open WebUI instances, security teams, and IT administrators should be aware of this vulnerability and take necessary actions to protect their systems. They should prioritize verifying if their Open WebUI instances are vulnerable and upgrading to version 0.11.1 or later. Additionally, they should monitor for suspicious activity, review system logs, and develop a remediation plan to address potential DoS attacks.

Why it matters

CVE-2026-88000 is a vulnerability in Open WebUI that could lead to a denial-of-service (DoS) condition. Defenders should prioritize verifying if their Open WebUI instances are vulnerable and upgrading to version 0.11.1 or later.

• Potential denial-of-service (DoS) attacks against Open WebUI instances
• Blocked user requests due to infinite loop
• Possible data loss or corruption due to blocked requests
• Verification of vulnerability and remediation efforts required

Technical summary

The vulnerability exists in Open WebUI versions from 0.10.0 to 0.11.0. An authenticated user can store a cyclic chat tree and delete a message, causing a synchronous infinite loop on the server request loop that blocks every user's requests until the process is killed. The issue is fixed in version 0.11.1. This vulnerability could lead to a denial-of-service (DoS) condition, impacting the availability of Open WebUI instances. Defenders should prioritize verifying if their Open WebUI instances are vulnerable and upgrading to version 0.11.1 or later.

Defensive priority

Defenders should prioritize verifying if their Open WebUI instances are vulnerable and upgrading to version 0.11.1 or later. They should also monitor for any suspicious activity, such as unusual chat tree structures or message deletion attempts.

Recommended defensive actions

• Verify if Open WebUI instances are vulnerable and upgrade to version 0.11.1 or later
• Monitor for suspicious activity, such as unusual chat tree structures or message deletion attempts
• Review and update incident response plans to address potential DoS attacks
• Perform vulnerability scanning and penetration testing to identify potential entry points
• Implement compensating controls, such as rate limiting or IP blocking
• Review system logs for signs of exploitation
• Develop a remediation plan and assign responsibilities to relevant teams

Evidence notes

The vulnerability was reported by an unknown source and fixed in version 0.11.1. The CVE record and NVD entry provide details on the vulnerability. Further information is limited, but defenders should verify Open WebUI instances for vulnerability and review chat tree structures for potential cyclic patterns. Evidence limits suggest verifying instances and monitoring for suspicious activity.

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.