{"api_version":"1","generated_at":"2026-08-20T23:53:03+00:00","cve":"CVE-2026-74905","urls":{"html":"https://cve.report/CVE-2026-74905","api":"https://cve.report/api/cve/CVE-2026-74905.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-74905","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-74905"},"summary":{"title":"SiYuan before v3.7.4 SSRF via IPv6 Transition Address Bypass","description":"SiYuan before v3.7.4 contains a server-side request forgery (SSRF) vulnerability in the isPrivateIP function in kernel/util/net.go, used by SSRFSafeDialer to enforce SSRF protection in SafeMode. The function only checks for loopback, link-local unicast, private, and unspecified addresses and does not recognize IPv6 transition addresses (NAT64 64:ff9b::/96, 6to4 2002::/16, Teredo 2001::/32) that embed private IPv4 destinations. 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