The forwarded module is used by the Express.js framework to handle the X-Forwarded-For header. It is vulnerable to a regular expression denial of service when it's passed specially crafted input to parse. This causes the event loop to be blocked causing a denial of service condition.
No PoCs from references.
- https://github.com/ARPSyndicate/cvemon
- https://github.com/ossf-cve-benchmark/CVE-2017-16118