CVE-2026-61704
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.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 33% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 7.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N- Weakness
- CWE-918
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-08-20
- Last modified
- 2026-09-18
- Sources
- NVD
References
- https://github.com/OP-Engineering/link-preview-js/commit/6ee25043dd60b097eb70b4ce049aac94b28239e3
- https://github.com/OP-Engineering/link-preview-js/commit/f3a3dd84adbb9d32d06a933f44ff3eaa837f9a12
- https://github.com/OP-Engineering/link-preview-js/pull/181
- https://github.com/OP-Engineering/link-preview-js/releases/tag/4.0.4
- https://github.com/OP-Engineering/link-preview-js/security/advisories/GHSA-cpjf-6666-r8fx