{"api_version":"1","generated_at":"2026-08-20T21:21:17+00:00","cve":"CVE-2026-73253","urls":{"html":"https://cve.report/CVE-2026-73253","api":"https://cve.report/api/cve/CVE-2026-73253.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-73253","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-73253"},"summary":{"title":"Mongoose: TLS Hostname Verification Bypass via Overly Permissive Wildcard Matching","description":"Mongoose is an embedded web server and network library. Prior to version 7.22, an on-path network attacker with a wildcard certificate for a parent domain can impersonate deeper subdomains to a client using the built-in TLS stack. The mg_tls_verify_cert_san() and mg_tls_verify_cert_cn() functions in src/tls_builtin.c call mg_match(), whose wildcard can cross DNS label boundaries, so a pattern such as *.example.com can match foo.bar.example.com. 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