GHSA-jw37-5gqr-cf9j is a critical-severity (CVSS 9.1) Server-Side Request Forgery (SSRF) vulnerability in ftp-srv. O3 Security confirms whether GHSA-jw37-5gqr-cf9j is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Server-Side Request Forgery in ftp-srv
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
ftp-srvnpmDescription
Background
The FTP protocol creates two connections, one for commands and one for transferring data. This second data connection can be created in two ways, on the server by sending the PASV command, or on the client by sending the PORT command.
The PORT command sends the IP and port for the server to connect to the client with.
Issue
Since the client can send an arbitrary IP with the PORT command, this can be used to cause the server to make a connection elsewhere.
Patches
- fix: disallow PORT connections to alternate hosts: e449e75219d918c400dec65b4b0759f60476abca
Deprecation notices have been published for older versions.
Workarounds
Blacklisting the FTP Command PORT will prevent the server from exposing this behaviour through active connections until a fix is applied.
const ftp = new FtpSrv({
blacklist: ['PORT']
});
References
https://www.npmjs.com/advisories/1445
Credits
Thank you to; @trs for fixing it @andreeleuterio for reporting it to us for an anonymous user (Vincent) through the NPM platform @quiquelhappy for bringing it to our attention after it slipped through the cracks during Christmas
For more information
If you have any questions or comments about this advisory:
- Open an issue at https://github.com/autovance/ftp-srv
- Email us directly; [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | ftp-srv | ≥ 1.0.0&&< 2.19.6 | 2.19.6 |
| 📦npm | ftp-srv | ≥ 3.0.0&&< 3.1.2 | 3.1.2 |
| 📦npm | ftp-srv | ≥ 4.0.0&&< 4.3.4 | 4.3.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ftp-srv. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update ftp-srv to 2.19.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-jw37-5gqr-cf9j is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-jw37-5gqr-cf9j is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-jw37-5gqr-cf9j. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-jw37-5gqr-cf9j in your dependencies?
O3 detects GHSA-jw37-5gqr-cf9j across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.