Description
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.11.0, Open WebUI resolved a hostname during URL validation and rejected private, loopback, and link-local addresses, but the HTTP clients resolved the hostname again at connection time. An authenticated attacker who controlled authoritative DNS for a submitted hostname could answer with a public address during validation and an internal one during connection, reaching cloud metadata, loopback admin APIs, or internal services through URL ingest, chat image_url fetches, image editing, or OAuth profile-picture fetches, with most paths returning the response to the attacker and the OAuth path forwarding the OAuth access token. This issue is fixed in 0.11.0.
Affected products
openwebui: open webui
References2
- github.com/open-webui/open-webui/security/advisories/GHSA-h6x2-… PatchVendor Advisory
- github.com/open-webui/open-webui/releases/tag/v0.11.0 Release Notes
Metrics
- CVSS 3.1
-
6.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 17 · as of 13 November 2026
- CWE
- CWE-367CWE-918
Could this be exploited in your environment?
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