Advisories for Npm/Link-Preview-Js package

The existing advisory GHSA-4gp8-rjrq-ch6q / CVE-2026-43897 states that the SSRF issue was fixed in 4.0.1. However, 4.0.3 remains bypassable when the documented resolveDNSHost mitigation is used. Root cause: The library validates one resolved IP address through resolveDNSHost, but later performs fetch() against the original hostname without pinning the connection to the validated IP. An attacker-controlled DNS server can return a public IP during validation and a loopback/internal IP during the …

The library did not check for IPv6 loopback attacks. There was also a DNS attack, where an address could be resolved into an internal IP. This could cause internal data leaks.

The package link-preview-js before 2.1.16 is vulnerable to Server-side Request Forgery (SSRF) which allows attackers to send arbitrary requests to the local network and read the response. This is due to flawed DNS rebinding protection.