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CVE-2026-54007 open-webui CVE debrief

CVE-2026-54007 is a high-severity vulnerability in Open WebUI, a self-hosted artificial intelligence platform. Prior to version 0.9.6, the chat message listener allows non-same-origin input:prompt and action:submit messages, enabling an external site to set prompt text and trigger submitPrompt() in an authenticated victim session. This allows for cross-site forced actions and model/tool execution under victim privileges without consent. The vulnerability was validated with a cross-origin attacker page that auto-posted messages, causing unauthorized POST /api/v1/chats/new and POST /api/chat/completions requests containing attacker-controlled prompts. The issue is fixed in version 0.9.6.

Vendor
open-webui
Product
Unknown
CVSS
HIGH 7.1
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-23
Original CVE updated
2026-06-26
Advisory published
2026-06-23
Advisory updated
2026-06-26

Who should care

Security teams and administrators of Open WebUI instances should be aware of this vulnerability. If Open WebUI is used in an environment where users have access to sensitive data or systems, defenders should prioritize patching to version 0.9.6 or later. Additionally, defenders should monitor for suspicious activity and implement compensating controls to detect and prevent exploitation.

Technical summary

The vulnerability exists in the chat message listener of Open WebUI, which allows non-same-origin input:prompt and action:submit messages. This enables an external site to set prompt text and trigger submitPrompt() in an authenticated victim session, leading to cross-site forced actions and model/tool execution under victim privileges. The issue arises from inadequate origin checks on incoming messages. The vulnerability is characterized by CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X, with a CVSS score of 7.1 and HIGH severity.

Defensive priority

Defenders should prioritize patching Open WebUI to version 0.9.6 or later. In the interim, defenders can implement network access controls and monitor for suspicious activity.

Recommended defensive actions

  • Patch Open WebUI to version 0.9.6 or later
  • Implement network access controls to restrict access to Open WebUI
  • Monitor for suspicious activity and implement compensating controls to detect and prevent exploitation
  • Conduct a thorough review of Open WebUI configurations and user privileges
  • Consider implementing additional security measures, such as web application firewalls or intrusion detection systems

Evidence notes

The vulnerability was reported and patched in version 0.9.6. The CVE record and NVD detail provide additional information on the vulnerability. The source item URL provides further details on the vulnerability and its mitigation.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-54007 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-54007

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-54007 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-54007

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental 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.