LoFP LoFP / false positives may be present if domain name is similar to dga generated domains.

Techniques

Sample rules

Detect DGA domains using pretrained model in DSDL

Description

The following analytic identifies Domain Generation Algorithm (DGA) generated domains using a pre-trained deep learning model. It leverages the Network Resolution data model to analyze domain names and detect unusual character sequences indicative of DGA activity. This behavior is significant as adversaries often use DGAs to generate numerous domain names for command-and-control servers, making it harder to block malicious traffic. If confirmed malicious, this activity could enable attackers to maintain persistent communication with compromised systems, evade detection, and execute further malicious actions.

Detection logic


| tstats `security_content_summariesonly` values(DNS.answer) as IPs min(_time) as firstTime  max(_time) as lastTime from datamodel=Network_Resolution by DNS.src, DNS.query 
| `drop_dm_object_name(DNS)` 
| rename query AS domain 
| fields IPs, src, domain, firstTime, lastTime 
| apply pretrained_dga_model_dsdl 
| rename pred_dga_proba AS dga_score 
| where dga_score>0.5 
| `security_content_ctime(firstTime)`  
| `security_content_ctime(lastTime)` 
| table src, domain, IPs, firstTime, lastTime, dga_score 
| `detect_dga_domains_using_pretrained_model_in_dsdl_filter`