Open WebUI: Any authenticated user can reach internal services and cloud metadata via NAT64-encoded URLs

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.1 · CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N

EPSS

• CVE-2026-70485: 0.35% estimated exploitation activity in the next 30 days; percentile 28.78 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Open WebUI fetches user-supplied URLs on the server for RAG URL ingestion, URL-to-markdown conversion and web-search content retrieval, and decides whether a destination is allowed by asking whether its IP address is globally routable. That test operates on the literal IPv6 address and does not look at the IPv4 address embedded inside it. On a deployment whose network has a NAT64 gateway, any verified user can wrap an internal or cloud-metadata IPv4 address in the NAT64 well-known prefix, pass the filter, and receive the internal response body back through the API. Preconditions - Any verified (authenticated) user account. No admin role, no elevated permission. - Default configuration: ENABLELOCALWEBFETCH off, the default WEBFETCHFILTERLIST metadata blocklist in place. Neither prevents this, because the blocklist matches hostname strings and the NAT64 literal is not one of them. - The deployment's network must provide NAT64 translation for the well-known 64:ff9b::/96 prefix,…

Published by the source

4 Aug 2026, 19:59 UTC

Last modified by the source

4 Aug 2026, 19:59 UTC

Source last checked

26 Oct 2026, 13:50 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-8x5v-cpv7-8jjp

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# Patch Next advisory brief: CVE-2026-70485

Advisory: Open WebUI: Any authenticated user can reach internal services and cloud metadata via NAT64-encoded URLs
IDs: CVE-2026-70485, GHSA-8x5v-cpv7-8jjp
Record: https://patchnext.com/advisories/cve-2026-70485 (revision 1, source checked 26 Oct 2026, 13:50 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: open-webui 0.11.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI open-webui: affected >= 0.9.0, < 0.11.0; fixed in 0.11.0

## Suggested inspection (read-only)
- `python -m pip show open-webui`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on open-webui.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-8x5v-cpv7-8jjp (GitHub-reviewed advisory GHSA-8x5v-cpv7-8jjp lists affected ranges: PyPI open-webui >=0.9.0 <0.11.0)

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