Vulnerability · Published Oct 23, 2026 · Assigned by EEF
CVE-2026-107685WebSocket sessions do not verify TLS certificates, exposing API keys and OAuth tokens to on-path attackers
Critical 9.1
In plain English
A critical-severity improper certificate validation in req_llm from agentjido. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 20% of all known vulnerabilities).
Official description
Improper Certificate Validation vulnerability in the WebSocket streaming client in agentjido req_llm allows an on-path attacker to read and modify OpenAI WebSocket sessions, including the authorization bearer token, via a TLS certificate the client does not trust. ReqLLM.Streaming.WebSocketSession.Client.start/3 in lib/req_llm/streaming/web_socket_session/client.ex starts WebSockex without TLS options, and WebSockex defaults to insecure: true, which connects with verify: :verify_none. The option allowlist also drops any caller-supplied cacerts or ssl_options, so an application cannot turn verification on. The OpenAI Responses, Realtime, and Codex WebSocket paths reach this client and send the API key or OAuth access token in the authorization header. HTTP streaming through Finch and the HTTP/2 duplex session through Mint verify certificates and are not affected. This issue affects req_llm: from 1.9.0 before 1.29.0.
Affected products (as reported)
Weakness: CWE-295 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
References
- WebSocket sessions do not verify TLS certificates, exposing API keys and OAuth tokens to on-path attackers vendor-advisory, related
- EEF CNA record for CVE-2026-107685 related
- OSV record EEF-CVE-2026-107685 related
- Introducing commit a389d71 in agentjido/req_llm related
- Fix commit c7264fc in agentjido/req_llm patch