Intel

AIKIDO-2026-10511

webfinger.js is vulnerable to Server-Side Request Forgery (SSRF)

Server-Side Request Forgery (SSRF) Pre-CVE
Found by Aikido Intel before public disclosure or CVE publication.
Published Apr 23, 2026

66

Medium Risk

This Affects:

JSwebfinger.js
0.0.1 - 3.0.3
Fixed in 3.0.4
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TL;DR

Affected versions of this package are vulnerable to server-side request forgery (SSRF) due to improper parsing and validation of user-supplied WebFinger addresses. The affected lookup logic derives request targets from externally controlled input without sufficiently restricting host, path, or private network destinations, allowing crafted addresses to redirect outbound requests to localhost, internal services, or arbitrary endpoints. An attacker able to supply malicious lookup values can cause the application to initiate unauthorized network requests, potentially exposing internal resources or enabling blind SSRF attacks.

Who does this affect?

You are affected if you are using a version that falls within the vulnerable range.

Background info

webfinger.js is vulnerable to Server-Side Request Forgery (SSRF) in versions 0.0.1 - 3.0.3.

How to fix this

Upgrade the webfinger.js library to the patch version.