CVE-2026-59714: Open WebUI: Cross-channel message overwrite via chat completion API (single-model and multimodel message_ids)
Any authenticated user can overwrite the content of a message in a channel they do not belong to (including private and DM channels) by sending a chat completion request with a channel:-prefixed chat_id and a target message_id. The channel: path routes pipeline output through _make_channel_emitter, which writes to the Messages table using the caller-supplied message_id without binding it to the channel.
This advisory consolidates two filings of the same flaw: the original single-model form, and a multimodel message_ids variant that survives the partial fix shipped in v0.9.6 (see “Fix status” below).
References
- github.com/advisories/GHSA-x2ff-v5v8-m75m
- github.com/open-webui/open-webui/commit/33e4e0dcc43afcca80f9c635d762cdc76c768ba9
- github.com/open-webui/open-webui/commit/ac3449cac91e62b08a7c28e54fcd044d14dea791
- github.com/open-webui/open-webui/releases/tag/v0.10.0
- github.com/open-webui/open-webui/security/advisories/GHSA-x2ff-v5v8-m75m
- nvd.nist.gov/vuln/detail/CVE-2026-59714
Code Behaviors & Features
Detect and mitigate CVE-2026-59714 with GitLab Dependency Scanning
Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →