Synthèse
Attackers sometimes use DNS tunneling to bypass firewalls by encoding sensitive data (like passwords or SSH keys) into DNS queries. Instead of a normal request like google.com, the logs will show long, encoded strings. Look for an unusually high volume of queries for unique, long, and high-entropy subdomains by examining the fields: QueryName: Look for strings like h3ldo293js92.example.com, QueryType: Often uses TXT, CNAME, or NULL records to carry the payload, and ClientIP: Identify if a single
Attackers sometimes use DNS tunneling to bypass firewalls by encoding sensitive data (like passwords or SSH keys) into DNS queries. Instead of a normal request like google. com, the logs will show long, encoded strings. Look for an unusually high volume of queries for unique, long, and high-entropy subdomains by examining the fields: QueryName: Look for strings like h3ldo293js92. example.
com, QueryType: Often uses TXT, CNAME, or NULL records to carry the payload, and ClientIP: Identify if a single internal host is generating thousands of these unique requests. Additionally, attackers may attempt to leak sensitive data by hiding it within non-standard protocols or by using common protocols (like DNS or ICMP) in unusual ways to bypass standard firewalls. Discover this by querying the magic_ids_detections logs to look for signatures that flag protocol anomalies, such as "ICMP tunneling" or "DNS tunneling" detections in the SignatureMessage. Whether you are investigating a zero-day vulnerability or tracking a sophisticated botnet, the data you need is now at your fingertips.
Source originale
h3ldo293js92.example.com
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