bad-hersfeld.de

Delegation · all IPv4 addresses are in 212.218.193.0/24. A single network failure takes all nameservers down; RFC 2182 recommends topologically separate networks (anycast setups are an exception).

Delegation · None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.

Nameservers · These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: cns-nbg1-mhef.nethinks.com: "9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.16.tuxcare.els19"; cp-nbg1-mhef.nethinks.com: "9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.16.tuxcare.els19". Hide or replace the version string.

SOA · retry 1h should be shorter than refresh 1h; expire 1d is shorter than 7d; secondaries stop answering too soon when the primary is down. Current values: refresh 1h, retry 1h, expire 1d, negative TTL 1h.

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.

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 record has no rua tag, so you receive no aggregate reports about who sends mail as your domain. Add rua=mailto:...

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

MX · These MX addresses have no PTR record, which many receivers treat as a spam signal: 2001:4cd8:1:a001::66 (mailrelay.nethinks.com). Ask your hosting provider to set one.

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.