CVE-2025-23221 — Fedify has an Infinite loop and Blind SSRF found inside the Webfinger mechanism
Fedify is a TypeScript library for building federated server apps powered by ActivityPub and other standards. This vulnerability allows a user to maneuver the Webfinger mechanis…
Published: 2025-01-20 · CVSS: 5.4 · CVSS 3.1
Fedify is a TypeScript library for building federated server apps powered by ActivityPub and other standards. This vulnerability allows a user to maneuver the Webfinger mechanism to perform a GET request to any internal resource on any Host, Port, URL combination regardless of present security mechanisms, and forcing the victim’s server into an infinite loop causing Denial of Service. Moreover, this issue can also be maneuvered into performing a Blind SSRF attack. This vulnerability is fixed in 1.0.14, 1.1.11, 1.2.11, and 1.3.4.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7