{"id":"CVE-2026-79671","aliases":["GHSA-r2x7-427f-rq69","GO-2026-5603"],"url":"https://o3.security/vulnerability/CVE-2026-79671","summary":"Ech0 before 4.4.3 SSRF via DNS Resolution Bypass","details":"Ech0 before 4.4.3 contains a server-side request forgery vulnerability in the validateWebhookURL function (webhook_setting_service.go), which only validates literal IP addresses via net.ParseIP() and fails to reject hostnames that DNS-resolve to private or internal IPs (e.g., 169.254.169.254.nip.io). An attacker with admin privileges can create a webhook with such a hostname to bypass validation and cause the server to make requests to internal services, cloud metadata endpoints, and private network resources. The issue is fixed in 4.4.3.","published":"2026-08-25T11:33:32.174Z","modified":"2026-09-02T03:30:41.466285738Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Go","name":"github.com/lin-snow/ech0","fixedVersion":"4.4.3"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/79xxx/CVE-2026-79671.json"},{"type":"ADVISORY","url":"https://github.com/lin-snow/Ech0/security/advisories/GHSA-r2x7-427f-rq69"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-79671"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/ech0-before-ssrf-via-dns-resolution-bypass"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-02T03:30:41.466285738Z"}}