{"id":"GHSA-cpjf-6666-r8fx","summary":"link-preview-js DNS Rebinding SSRF Bypass / Incomplete Fix for CVE-2026-43897","details":"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.\n\nRoot cause:\nThe 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 final connection.\n\nImpact:\nThis allows an attacker to bypass the documented SSRF mitigation and make the server-side fetch reach loopback or internal addresses under DNS rebinding conditions.\n\nThis appears to be either an incomplete fix for CVE-2026-43897 or a new DNS rebinding SSRF bypass affecting the latest version.\n\nThe PoC was reproduced in a local-only controlled environment to avoid targeting production or third-party systems. Evidence and reproduction details can be provided privately.","aliases":["CVE-2026-61704"],"modified":"2026-09-02T21:45:09.841015611Z","published":"2026-09-02T21:29:57Z","database_specific":{"github_reviewed":true,"github_reviewed_at":"2026-09-02T21:29:57Z","nvd_published_at":"2026-08-20T17:18:51Z","cwe_ids":["CWE-918"],"severity":"HIGH"},"references":[{"type":"WEB","url":"https://github.com/OP-Engineering/link-preview-js/security/advisories/GHSA-cpjf-6666-r8fx"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-61704"},{"type":"WEB","url":"https://github.com/OP-Engineering/link-preview-js/pull/181"},{"type":"WEB","url":"https://github.com/OP-Engineering/link-preview-js/commit/6ee25043dd60b097eb70b4ce049aac94b28239e3"},{"type":"WEB","url":"https://github.com/OP-Engineering/link-preview-js/commit/f3a3dd84adbb9d32d06a933f44ff3eaa837f9a12"},{"type":"PACKAGE","url":"https://github.com/OP-Engineering/link-preview-js"},{"type":"WEB","url":"https://github.com/OP-Engineering/link-preview-js/releases/tag/4.0.4"}],"affected":[{"package":{"name":"link-preview-js","ecosystem":"npm","purl":"pkg:npm/link-preview-js"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"4.0.4"}]}],"database_specific":{"last_known_affected_version_range":"\u003c= 4.0.3","source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-cpjf-6666-r8fx/GHSA-cpjf-6666-r8fx.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"}]}