CVE-2026-70485 open-webui CVE debrief

Who should care

Defenders and administrators of Open WebUI deployments, especially those with NAT64 gateways, should assess their exposure and ensure the platform is updated to version 0.11.0 or later.

Why it matters

CVE-2026-70485 allows verified users in Open WebUI deployments with NAT64 gateways to potentially access internal or cloud-metadata IPv4 addresses, leading to unauthorized information disclosure. Defenders should verify their deployments' configurations and versions, and ensure they are updated to version 0.11.0 or later.

• Potential unauthorized disclosure of internal or cloud-metadata information.
• Possible bypass of security filters due to improper URL validation.
• Verification of Open WebUI deployment configurations and versions is necessary.
• Ensuring updates to version 0.11.0 or later is crucial for mitigation.

Technical summary

The Open WebUI platform had a vulnerability where it did not properly validate user-supplied URLs for global routability, specifically with IPv6 addresses and embedded IPv4 addresses. This allowed verified users to access internal or cloud-metadata IPv4 addresses via NAT64 gateways. The issue was fixed in version 0.11.0. Defenders should prioritize verifying their Open WebUI deployments for exposure, especially those with NAT64 gateways, and ensure they are running version 0.11.0 or later. The vulnerability could lead to unauthorized information disclosure, and defenders should assess their exposure and ensure the platform is updated.

Defensive priority

Defenders should prioritize verifying their Open WebUI deployments for exposure, especially those with NAT64 gateways, and ensure they are running version 0.11.0 or later.

Recommended defensive actions

• Verify Open WebUI deployment versions and configurations for exposure, especially with NAT64 gateways.
• Ensure Open WebUI is updated to version 0.11.0 or later.
• Monitor for unusual URL ingestion, conversion, or retrieval activities.
• Review and restrict access to internal or cloud-metadata IPv4 addresses.
• Perform a thorough review of Open WebUI deployment configurations to identify potential exposure.
• Implement compensating controls for exposed systems while remediation is scheduled and verified.
• 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, its impact, and the fix in version 0.11.0. However, there is limited information on actual exploitation or affected deployments. Defenders should verify Open WebUI deployment configurations and versions, focusing on those with NAT64 gateways, and ensure they are updated to version 0.11.0 or later. Evidence from the CVE record and NVD entry suggests that the vulnerability allows verified users to access internal or cloud-metadata IPv4 addresses via NAT64 gateways, which

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.