Server-side Request Forgery (SSRF) Affecting webfinger.js package, versions <2.8.1


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

Exploit Maturity
Proof of Concept

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  • Snyk IDSNYK-JS-WEBFINGERJS-11345662
  • published1 Aug 2025
  • disclosed28 Jul 2025
  • creditOri Hollander

Introduced: 28 Jul 2025

NewCVE-2025-54590  (opens in a new tab)
CWE-918  (opens in a new tab)

How to fix?

Upgrade webfinger.js to version 2.8.1 or higher.

Overview

webfinger.js is an A client library to query WebFinger records

Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the WebFinger class. An attacker can cause the server to send arbitrary GET requests to internal or external hosts, including localhost and LAN addresses, by supplying a specially crafted user address.

Note: This is a Blind-SSRF and the response of the request it not returned to the user.

PoC

curl "http://localhost:3000/api/v1/search_user?search=user@localhost:1234/secret.txt?"

References

CVSS Base Scores

version 4.0
version 3.1