Affected versions of featurebook resolve relative file paths, resulting in a directory traversal vulnerability. A malicious actor can use this vulnerability to access files outside of the intended directory root, which may result in the disclosure of private files on the vulnerable system.

The featurebook package is not intended to be run in production code nor to be exposed to an untrusted network.

Proof of Concept

GET /../../../../../../../../../../etc/passwd HTTP/1.1
host:foo

Recommendation

No direct patch is currently available.

At this time, the best mitigation is to ensure that featurebook is not running in production or exposed to an untrusted network.

References

• https://hackerone.com/reports/296305
• https://www.npmjs.com/advisories/556