Server-side Request Forgery (SSRF) Affecting is-localhost-ip package, versions *
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applicationsSnyk Learn
Learn about Server-side Request Forgery (SSRF) vulnerabilities in an interactive lesson.
Start learning- Snyk IDSNYK-JS-ISLOCALHOSTIP-13004668
- published23 Sept 2025
- disclosed22 Sept 2025
- creditCristian Vargas
Introduced: 22 Sep 2025
NewCVE-2025-9960 (opens in a new tab)How to fix?
There is no fixed version for is-localhost-ip.
Overview
is-localhost-ip is a Checks whether given DNS name or IPv4/IPv6 address belongs to a local machine
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the isLocalhost() function which misclassifies IP addresses and allows localhost checks to be bypassed. An attacker can access internal network resources by using alternative representations such as IPv6-mapped IPv4 addresses (e.g.,::ffff:127.0.0.1), allowing restricted localhost access to be incorrectly permitted.