23 Oct 2026 15:48:27 UTC
Headroom vulnerable to Cross-Site WebSocket Hijacking (CSWSH)
cve-program · CVE-2026-71416 · Published
CVE-2026-71416
Headroom vulnerable to Cross-Site WebSocket Hijacking (CSWSH)
CVSS 3.1 8.8 HIGHCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-71416
PublishedHeadroom compresses data before the data reaches a large language model. Prior to version 0.35.0, the Headroom WebSocket server does not validate the `Origin` header of incoming client WebSocket requests before forwarding the request to the upstream server, allowing malicious WebSocket clients to perform arbitrary LLM requests without authentication. This can be exploited by a malicious WebSocket client executed in a traditional or headless browser such as lightpanda, if the browser has access to the Headroom proxy and the OpenAI API key is stored in the `OPENAI_API_KEY` environment variable. Version 0.35.0 fixes the issue.
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