Classification:

attack

Tactic:

TA0011-command-and-control

Technique:

T1071-application-layer-protocol

VIEW RULE IN DATADOG VIEW SIGNALS

Goal

Trigger an alert when a high volume of ANY type allowed requests is detected from a source.

Strategy

This rule continuously monitors DNSFilter Traffic logs and triggers an alert when a high volume of allowed ANY-type requests is detected from a source. It helps identify devices that are sending an unusually high number of DNS queries using the ANY request type. A high volume of ANY type DNS requests may indicate DNS amplification attacks, as legitimate clients rarely use ANY queries in large volumes.

Triage and Response

1. Review DNSFilter Traffic logs to identify the source associated with generation of the high number of ANY-type DNS queries.
2. Analyze domain, user {{@usr.name}}, and policy {{@policy_name}} to understand patterns, user info, and policy related to this behavior.
3. If malicious domains are identified, isolate the device, perform a malware scan, and block associated domains or IPs.
4. Update DNSFilter blocklists or filtering policies as needed, and continue monitoring for recurring blocked activity.