code-server session cookie can be extracted by having user visit specially crafted proxy URL
code-server runs VS Code on any machine anywhere through browser access. Prior to version 4.99.4, a maliciously crafted URL using the proxy subpath can result in the attacker gaining access to the session token. Failure to properly validate the port for a proxy request can result in proxying to an arbitrary domain. The malicious URL `https://<code-server>/proxy/[email protected]/path` would be proxied to `[email protected]/path` where the attacker could exfiltrate a user's session token. Any user who runs code-server with the built-in proxy enabled and clicks on maliciously crafted links that go to their code-server instances with reference to /proxy
Versions of the package code-server before 4.10.1 are vulnerable to Missing Origin Validation in WebSockets handshakes. Exploiting this vulnerability can allow an adversary in specific scenarios to access data from and connect to the code-server instance.