Client-Side Enforcement of Server-Side Security vulnerability in the WebSocket connection handling of mtrudel bandit allows a remote client to keep running WebSock handler code after the server has stopped its connection, via data frames sent after ignoring the server's Close frame.
When a WebSock callback returns {:stop, ...}, Bandit.WebSocket.Connection calls terminate/2, sends Close and shuts down the write side, but keeps the connection process running in a :closing state. handle_frame/3 and handle_info/3 never check that state, so later frames still reach handle_in/2 and later messages reach handle_info/2, with the state from the stop tuple, until the client sends Close, TCP drops or the idle timeout fires. A client refused in init/1 after a failed token check could still run an admin-only action.
This issue affects bandit: from 0.5.1 before 1.14.0.
CVSS
No CVSS.
References
Configurations
No configuration.
History
26 Oct 2026, 14:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-10-26 14:16
Updated : 2026-10-26 16:59
NVD link : CVE-2026-110314
Mitre link : CVE-2026-110314
CVE.ORG link : CVE-2026-110314
JSON object : View
Products Affected
No product.
CWE
CWE-602
Client-Side Enforcement of Server-Side Security
