CVE-2026-87995 open-webui CVE debrief

Who should care

Defenders responsible for Open WebUI instances, especially those with shared terminal servers, should assess exposure and prioritize remediation. This includes verifying instance versions, ensuring proper security controls are in place, and planning for upgrades to version 0.11.1 or later. Security teams and vulnerability management teams should also review the vulnerability's impact on their environments and take appropriate actions to mitigate the risk.

Why it matters

CVE-2026-87995 is a high-severity vulnerability in Open WebUI that allows potential account takeover via malicious script hosting, especially in shared terminal server environments. Defenders should prioritize verifying exposure and upgrading to version 0.11.1 or later.

• Potential account takeover via malicious script hosting
• Increased risk for shared terminal servers
• Need for verification of instance version and exposure
• Priority on upgrading to version 0.11.1 or later

Technical summary

The vulnerability exists in Open WebUI versions 0.8.11 to 0.11.1, where the platform's terminal port content rendering in an iframe sandbox with allow-scripts and allow-same-origin allows an authenticated user to host malicious scripts. When a victim opens the preview, the script can potentially take over the victim's account. This issue is fixed in version 0.11.1. The vulnerability has a CVSS score of 8.7, indicating high severity. Defenders should prioritize verifying exposure of Open WebUI instances, especially those with shared terminal servers, and ensure they are running version 0.11.1 or later.

Defensive priority

Defenders should prioritize verifying exposure of Open WebUI instances, especially those with shared terminal servers, and ensure they are running version 0.11.1 or later.

Recommended defensive actions

• Verify Open WebUI instance version and exposure
• Ensure shared terminal servers are properly secured
• Upgrade to version 0.11.1 or later
• Monitor for suspicious activity on shared terminals
• 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

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its CVSS score of 8.7 and affected versions. The vendor has released a patch in version 0.11.1. Open WebUI instances, especially those with shared terminal servers, should be verified for exposure. The vulnerability allows an authenticated user to host malicious scripts, potentially leading to account takeover when a victim opens the preview. Evidence from the CVE Program and NVD supports this assessment, and defenders should verify instance versions and plan

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.