generated: '2026-07-25' method: probed source: >- Live TLS handshakes, HTTP HEAD and dig queries against every host in apis.yml plus the JWKS host advertised by the d ACCOUNT Connect discovery document. Probed 2026-07-25. The registrable domain was corrected by hand to docomo.ne.jp — ne.jp is a Japanese second-level generic, not a registrable domain, and the automated pass had queried it. id.smt.docomo.ne.jp was also re-probed by hand: the automated pass recorded https:false because its handshake fails under a default OpenSSL 3 context (see below), not because the host lacks HTTPS. description: >- Transport and DNS security posture for NTT DOCOMO, Inc.'s public hosts. The headline finding is a split: the corporate host and the OIDC issuer negotiate TLS 1.3, but id.smt.docomo.ne.jp — the d ACCOUNT authorization endpoint host, where roughly 90 million users authenticate — caps at TLS 1.2, serves no HSTS, and rejects RFC 5746 secure renegotiation. Neither docomo.ne.jp nor nttdocomo.co.jp is DNSSEC-signed or publishes a CAA record. hosts: - host: www.docomo.ne.jp role: Corporate site and surviving public developer information page https: true tls_version: TLSv1.3 http_version: HTTP/2 cert_issuer: GlobalSign nv-sa cert_expires: Oct 19 04:19:21 2026 GMT hsts: true hsts_max_age: 15768000 hsts_include_subdomains: false hsts_preload: false - host: conf.uw.docomo.ne.jp role: d ACCOUNT Connect OpenID Provider (issuer, token, userinfo) https: true tls_version: TLSv1.3 http_version: HTTP/2 cert_issuer: DigiCert Inc cert_expires: Sep 30 23:59:59 2026 GMT hsts: false notes: >- Fronted by CloudFront over an AWS API Gateway origin (server openresty, apigw-requestid and x-amz-cf-id response headers). Returns 403 to every path except /.well-known/openid-configuration. - host: id.smt.docomo.ne.jp role: d ACCOUNT authorization endpoint and business documentation host https: true tls_version: TLSv1.2 tls13_supported: false http_version: HTTP/1.1 cert_issuer: GlobalSign nv-sa (GlobalSign RSA OV SSL CA 2018) cert_subject: C=JP, ST=Tokyo, L=Chiyoda-Ku, O=NTT DOCOMO.INC, CN=id.smt.docomo.ne.jp cert_expires: Sep 30 14:59:59 2026 GMT hsts: false secure_renegotiation: false notes: >- TLS 1.3 handshake fails (curl --tlsv1.3 --tls-max 1.3 returns no response); TLS 1.2 succeeds and serves HTTP 200. The server does not advertise the RFC 5746 renegotiation_info extension, so a default OpenSSL 3 client refuses the connection with UNSAFE_LEGACY_RENEGOTIATION_DISABLED. This is the host that carries the OIDC authorization endpoint /cgi8/oidc/authorize. - host: fr-end.oidc.if.cilite.docomo.ne.jp role: JWKS host for d ACCOUNT Connect https: true tls_version: TLSv1.3 http_version: HTTP/2 cert_issuer: GlobalSign nv-sa cert_expires: Sep 30 14:59:59 2026 GMT hsts: false domains: - domain: docomo.ne.jp dnssec: false caa: [] spf: true spf_policy: '~all' spf_record: >- v=spf1 +ip4:203.138.203.0/24 +ip4:210.153.87.192/29 +ip4:210.153.87.224/29 +ip4:202.212.37.97 +ip4:202.212.37.98 +ip4:202.212.37.100 +ip4:202.212.37.113 +ip4:202.212.37.103 +ip4:202.212.37.104 +ip4:1.73.231.0/26 +ip4:1.75.151.128/25 +ip4:1.75.146.128/25 +ip4:49.102.168.0/21 ~all dmarc: true dmarc_policy: quarantine dmarc_subdomain_policy: reject dmarc_pct: 100 dmarc_rua: mailto:docomo00001-ra@dmarc25.jp - domain: nttdocomo.co.jp dnssec: false caa: [] spf: true spf_policy: '~all' dmarc: true dmarc_policy: none dmarc_subdomain_policy: none dmarc_pct: 100 dmarc_rua: mailto:dm0mlsugqaev8.rua@dp.smtps.jp notes: >- The corporate domain runs DMARC in monitor mode (p=none) while the consumer/service domain enforces quarantine with sp=reject. findings: - severity: notable finding: >- id.smt.docomo.ne.jp — the d ACCOUNT authorization endpoint host — does not support TLS 1.3, sends no HSTS header, and lacks RFC 5746 secure renegotiation. - severity: notable finding: >- No CAA records on either registrable domain, so no certificate-authority issuance restriction is published. - severity: notable finding: No DNSSEC on docomo.ne.jp or nttdocomo.co.jp. - severity: informational finding: >- HSTS is present only on www.docomo.ne.jp, with a six-month max-age and neither includeSubDomains nor preload, so it does not protect the identity hosts.