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Delegation · all IPv4 addresses are in 83.171.239.0/24; all IPv6 addresses are in 2a05:8b81:1000::/48. A single network failure takes all nameservers down; RFC 2182 recommends topologically separate networks (anycast setups are an exception).

Nameservers · These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: ns14.linevast.com: "PowerDNS Authoritative Server 4.8.4 (built Feb 6 2024 20:17:27 by mockbuild@localhost)"; ns15.linevast.com: "PowerDNS Authoritative Server 4.8.4 (built Feb 6 2024 20:17:27 by mockbuild@localhost)"; ns16.linevast.com: "PowerDNS Authoritative Server 4.8.4 (built Feb 6 2024 20:17:27 by mockbuild@localhost)". Hide or replace the version string.

SOA · negative caching TTL (minimum) 3m20s is outside 5m–1d (RFC 2308 recommends 1–3 hours). Current values: refresh 1h, retry 10m, expire 14d, negative TTL 3m20s.

DNSSEC · The zone is not signed with DNSSEC, so answers can be spoofed. Enable DNSSEC at your DNS provider and publish the DS record at your registrar.

Records · These records have a TTL below 5m, causing extra queries and slower lookups: NS (3m20s). Low TTLs are useful just before a planned change. The NS TTL at the parent is 1d and in the zone 3m20s; resolvers may use either.

DNSSEC · DNSSEC is not enabled for this domain. Consider enabling DNSSEC to protect against DNS spoofing attacks.

MX · Only one MX record found. For better email reliability, consider adding at least one backup MX server.

DMARC · DMARC policy only applies to 25% of failing mail (pct=25). Raise pct to 100 once you are confident in your setup.

DKIM · 1024-bit RSA keys are the minimum and are considered weak today: k1 (1024 bits). Rotate to a 2048-bit key.

TLS · MTA-STS is not configured, so other mail servers fall back to unencrypted delivery when TLS fails or is stripped by an attacker. Publish a _mta-sts TXT record and a policy at https://mta-sts.<domain>/.well-known/mta-sts.txt.

TLS · MTA-STS or DANE is used without TLS-RPT, so you get no reports when senders fail to deliver because of TLS problems. Publish _smtp._tls TXT "v=TLSRPTv1; rua=mailto:...".