The vulnerability, classified as a Cross‑domain Redirection (CWE‑918), allows an authenticated user to cause the Open WebUI server to follow HTTP redirects to addresses that should be blocked, such as loopback, private networks, or cloud metadata services. Because the web fetch paths did not reapply the block list when redirects were enabled, an attacker can direct the server to retrieve data from internal resources and feed that data into web search, URL ingestion, page‑fetch tools, or chat image processing. This can expose internal system information or allow the attacker to bypass content restrictions.

The affected product is Open WebUI, versions 0.9.5 through 0.11.1 inclusive. These releases did not enforce the WEB_FETCH_FILTER_LIST or private‑address controls on redirect destinations when AIOHTTP_CLIENT_ALLOW_REDIRECTS was enabled.

The CVSS score is 5, indicating a medium severity. EPSS is not available, and the vulnerability is not listed in KEV. The flaw requires authentication, so an attacker must have valid user credentials. Once authenticated, the attacker can manipulate server‑side fetches to access internal hosts, potentially exposing sensitive data but not providing remote code execution or direct denial of service.