Insights & Articles

Technical analyses, incident reports and practical articles on cybersecurity, DNS security and IT infrastructure — straight from the field.

Incident AnalysisMay 5, 2026·Technical

DNSSEC Failure in the .de Zone: Why bahn.de, spiegel.de and blackfort-tec.de Returned SERVFAIL

Technical deep-dive into a DNSSEC incident at DENIC: malformed RRSIG for NSEC3 records, impact on validating resolvers, and lessons learned for security monitoring.

DNSSECDENICDNSSERVFAILNSEC3

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Plain EnglishMay 5, 2026·General

bahn.de and spiegel.de Unavailable: What Went Wrong with DNS Today

On May 5, 2026, many users could not reach bahn.de, spiegel.de and other .de websites – even though the internet was working fine. What happened? Explained without jargon.

DNSOutagebahn.despiegel.deDENIC

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