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.
CVE ID: CVE-2025-23221
CVSS Base Severity: MEDIUM
CVSS Base Score: 5.4
Vendor: dahlia
Product: fedify
EPSS Score: 0.06% (probability of being exploited)
EPSS Percentile: 29.09% (scored less or equal to compared to others)
EPSS Date: 2025-02-18 (when was this score calculated)