fitbook.de

Nameservers · These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: a1-130.akam.net: "41824.7"; a11-67.akam.net: "41824.5"; a11-67.akam.net: "41824.9"; a14-64.akam.net: "48878.29"; a14-64.akam.net: "48878.26"; a16-65.akam.net: "48878.27"; a16-65.akam.net: "48878.26"; a6-66.akam.net: "48878.29"; a6-66.akam.net: "48878.32"; a7-67.akam.net: "41824.8"; a7-67.akam.net: "41824.10". Hide or replace the version string.

DNSSEC · The earliest signature expires at 2026-10-27 18:27 UTC (in 140h0m0s). Check that automatic re-signing works.

DNSSEC · NSEC3 uses 15 iterations and a 8-byte salt. RFC 9276 recommends 0 iterations and no salt: extra iterations cost resolvers CPU and add no real protection, and some validators treat high counts as insecure.

SPF · SPF record uses ?all (neutral), which gives no protection against unauthorized senders. Use -all or ~all instead.

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

DMARC · DMARC subdomain policy is sp=none, so spoofed mail from subdomains is not blocked. Consider sp=quarantine or sp=reject.

DNSSEC · DNSKEY signatures expire at 2026-10-27T18:27:49Z (in 140h0m0s). Check that re-signing works.

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.