Vulnerability · Published May 15, 2026 · Assigned by GitHub_M

CVE-2026-44559Open WebUI: Missing Access Check on Channel Members Endpoint for Standard Channels

Medium 4.3

In plain English

A medium-severity missing authorization 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 0.2% (higher than 13% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.2%top 87.3% 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 0.9.0, the GET /api/v1/channels/{id}/members endpoint only checks membership for group and dm channel types (lines 467-469). For standard channels — including private ones — there is no channel_has_access check before returning the member list. Any authenticated user who knows a private channel's UUID can enumerate all users with access to that channel. This vulnerability is fixed in 0.9.0.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	open-webui	0.9.0	GHSA-c7wp-3qh5-55pv
PyPI	open-webui	0.9.0	PYSEC-2026-2720

Affected products (as reported)

Vendor	Product	Versions
open-webui	open-webui	< 0.9.0

Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

References

https://github.com/open-webui/open-webui/security/advisories/GHSA-c7wp-3qh5-55pv x_refsource_CONFIRM