CVE-2026-109294: Open WebUI 0.6.42 before 0.11.4 Memory Exhaustion via Compressed Remote Image
Open WebUI from 0.6.42 before 0.11.4 contains an uncontrolled resource consumption vulnerability that allows authenticated users to exhaust server memory by supplying compressed remote image URLs in chat messages. Attackers can point the image field at a host returning gzip-encoded responses, which getimagebase64fromurl decompresses unbounded, causing denial of service for all users.
Affected Software
Event History
Frequently Asked Questions
Who can exploit this issue?
An authenticated Open WebUI user can exploit it. The attacker needs to submit a chat message containing a remote image URL that points to a host serving a gzip-encoded response.
What deployments are affected?
Open WebUI versions from 0.6.42 before 0.11.4 are affected. The issue is network-reachable and does not require user interaction, but it does require low-level authenticated access.
What is the operational impact of a successful attack?
Unbounded decompression in get_image_base64_from_url can exhaust server memory. This can cause denial of service for all users of the affected Open WebUI instance.