Vulnerability · Published Jun 23, 2026 · Assigned by GitHub_M

CVE-2026-54009Open WebUI: Cross-user file disclosure via /api/chat/completions image_url field

Medium 6.5

In plain English

A medium-severity authorization bypass via user-controlled key in open-webui from open-webui. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.4%top 67.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, POST /api/chat/completions accepts an image_url.url value that, when it does NOT start with http://, https://, or data:image/, is interpreted as a file id and resolved against the global file table with no ownership check. an authenticated user can therefore set image_url.url to another user's file id, the server reads that file from disk, base64-encodes it, and injects the data URI into the LLM request. the user then prompts the LLM to describe / OCR the file and reads the content back. This vulnerability is fixed in 0.9.6.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	open-webui	0.9.6	GHSA-wch8-mhj5-9frg
PyPI	open-webui	0.9.6	PYSEC-2026-2766

Affected products (as reported)

Vendor	Product	Versions
open-webui	open-webui	< 0.9.6

Weakness: CWE-639 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

References

https://github.com/open-webui/open-webui/security/advisories/GHSA-wch8-mhj5-9frg x_refsource_CONFIRM