Description
Link Preview JS extracts web links information. Prior to 4.0.4, the resolveDNSHost mitigation in index.ts validates one resolved IP address but fetches the original hostname, allowing an attacker-controlled DNS server to return a public address during validation and a loopback or internal address during the final connection. This DNS rebinding condition bypasses the SSRF protection and can cause the server-side preview fetch to reach internal HTTP resources. Redirect handling is affected by the same validation-to-fetch mismatch. This issue is fixed in version 4.0.4.
References5
- github.com/OP-Engineering/link-preview-js/commit/6ee25043dd60b0…
- github.com/OP-Engineering/link-preview-js/commit/f3a3dd84adbb9d…
- github.com/OP-Engineering/link-preview-js/pull/181
- github.com/OP-Engineering/link-preview-js/releases/tag/4.0.4
- github.com/OP-Engineering/link-preview-js/security/advisories/G…
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 1% percentile: 46 · as of 10 November 2026
- CWE
- CWE-918
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.