Fedify has an Infinite loop and Blind SSRF found inside the Webfinger mechanism
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- Low · None · Low
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-835.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| dahlia | fedify | before 1.0.14; 1.1.0 to before 1.1.11; 1.2.0 to before 1.2.11; 1.3.0 to before 1.3.4 | 1.0.14, 1.1.11, 1.2.11, 1.3.4 | Patch available | CNA |
| — | @fedify/fedify (npm) | 1.0.13 to before 1.0.14 | 1.0.14 | Patch available | GHSA-c59p-wq67-24wx |
| — | @fedify/fedify (npm) | 1.1.10 to before 1.1.11 | 1.1.11 | Patch available | GHSA-c59p-wq67-24wx |
| — | @fedify/fedify (npm) | 1.2.10 to before 1.2.11 | 1.2.11 | Patch available | GHSA-c59p-wq67-24wx |
| — | @fedify/fedify (npm) | 1.3.3 to before 1.3.4 | 1.3.4 | Patch available | GHSA-c59p-wq67-24wx |
- fedify Vendordahlia Affected before 1.0.14; 1.1.0 to before 1.1.11; 1.2.0 to before 1.2.11; 1.3.0 to before 1.3.4 Fixed in 1.0.14, 1.1.11, 1.2.11, 1.3.4 Patch available CNA
- @fedify/fedify (npm) Vendor— Affected 1.0.13 to before 1.0.14 Fixed in 1.0.14 Patch available GHSA-c59p-wq67-24wx
- @fedify/fedify (npm) Vendor— Affected 1.1.10 to before 1.1.11 Fixed in 1.1.11 Patch available GHSA-c59p-wq67-24wx
- @fedify/fedify (npm) Vendor— Affected 1.2.10 to before 1.2.11 Fixed in 1.2.11 Patch available GHSA-c59p-wq67-24wx
- @fedify/fedify (npm) Vendor— Affected 1.3.3 to before 1.3.4 Fixed in 1.3.4 Patch available GHSA-c59p-wq67-24wx
Remediation
- Fix · CNA fedify (dahlia) Fixed in 1.0.14, 1.1.11, 1.2.11, 1.3.4
- Fix · GHSA-c59p-wq67-24wx @fedify/fedify (npm) Fixed in 1.0.14 Advisory →
- Fix · GHSA-c59p-wq67-24wx @fedify/fedify (npm) Fixed in 1.1.11 Advisory →
- Fix · GHSA-c59p-wq67-24wx @fedify/fedify (npm) Fixed in 1.2.11 Advisory →
- Fix · GHSA-c59p-wq67-24wx @fedify/fedify (npm) Fixed in 1.3.4 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2025-23221
- 2026-10-03 Alias added: GHSA-c59p-wq67-24wx
References
Other 5
- https://github.com/dahlia/fedify/security/advisories/GHSA-c59p-wq67-24wx
- https://github.com/dahlia/fedify/commit/8be3c2038eebf4ae12481683a1e809b314be3151
- https://github.com/dahlia/fedify/commit/c505eb82fcd6b5b17174c6659c29721bc801ab9a
- https://github.com/dahlia/fedify/commit/e921134dd5097586e4563ea80b9e8d1b5460a645
- https://github.com/dahlia/fedify
More dahlia vulnerabilities
- TI-2026-39357 @logtape/syslog: syslog log injection via unescaped control characters and unvalidated SD-NAME keys CVSS 3.1HIGH 8.6
- TI-2024-26611 Fedify vulnerable to allowing access to internal network resources CVSS 3.1HIGH 7.2
Sources
- CVE-2025-23221 · CVE Program
- CVE-2025-23221 · NVD
- FIRST EPSS
- GHSA-c59p-wq67-24wx · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences