HackMD · Domain Security

Hackmd Domain Security

Domain security

Domain security posture for HackMD, probed live across 1 host(s) and 1 registrable domain(s). 1 host(s) serve HTTPS (up to TLSv1.2); 1 advertise HSTS. Email/DNS controls: DNSSEC present, SPF present, DMARC present (p=reject).

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Transport & Host Security

hackmd.io
HTTPS: yes · TLS: TLSv1.2 · HSTS: yes · cert expires: Feb 2 23:59:59 2027 GMT

Domain (DNS/Email) Security

hackmd.io
DNSSEC: yes · SPF: yes · DMARC: yes (p=reject) · CAA: yes

Source

Domain Security

Raw ↑ 
generated: '2026-07-19'
method: probed
source: live DNS/TLS/HTTP probes of apis.yml + OpenAPI hosts
hosts:
- host: hackmd.io
  https: true
  tls_version: TLSv1.2
  cert_expires: Feb  2 23:59:59 2027 GMT
  hsts: true
  hsts_max_age: 31536000
domains:
- domain: hackmd.io
  dnssec: true
  caa:
  - 0 issuewild "amazontrust.com"
  - 0 issuewild "awstrust.com"
  - 0 issuewild "letsencrypt.org"
  - 0 iodef "mailto:support@hackmd.io"
  - 0 issuewild "amazon.com"
  - 0 issuewild "amazonaws.com"
  spf: true
  dmarc: true
  dmarc_policy: reject