ip 5uu8 com

Hunt Hypothesis

The rule detects potential command and control activity associated with the domain 5uu8.com, which may indicate malicious network communication. SOC teams should proactively hunt for this behavior in Azure Sentinel to identify and mitigate early-stage adversarial presence that could lead to data exfiltration or persistence.

YARA Rule

rule ip_5uu8_com {
    strings: $ = "\\x69\\x70\\x2e\\x35\\x75\\x75\\x38\\x2e\\x63\\x6f\\x6d"
    condition: any of them
}

Deployment Notes

This YARA rule can be deployed in the following contexts:

• Microsoft Defender for Endpoint — Custom indicators / advanced hunting
• Email Gateway — Attachment scanning
• File Share Monitoring — Periodic scanning of shared drives
• YARA CLI — Manual threat hunting on endpoints
• Source Rule

False Positive Guidance

• Scenario: Legitimate use of ip 5uu8 com during system diagnostics or network troubleshooting.
  Filter/Exclusion: Exclude processes associated with network diagnostic tools like ping, tracert, or nslookup.

• Scenario: Scheduled job running a script that temporarily resolves ip 5uu8 com as part of a domain validation process.
  Filter/Exclusion: Exclude processes initiated by task schedulers (e.g., schtasks.exe or at.exe) or scripts with known validation logic.

• Scenario: Administrative task involving DNS resolution for internal services, where ip 5uu8 com is a legitimate domain used in internal configurations.
  Filter/Exclusion: Exclude DNS-related processes such as dnscmd.exe, nslookup.exe, or dnsdiag.exe.

• Scenario: Use of ip 5uu8 com in a legitimate security tool for testing or sandboxing purposes.
  Filter/Exclusion: Exclude processes associated with security testing tools like Metasploit, Burp Suite, or Wireshark.

• Scenario: Legitimate use in a cloud environment where ip 5uu8 com is part of a service discovery or load balancing setup.
  Filter/Exclusion: Exclude processes related to cloud management tools like AWS CLI, Azure CLI, or Terraform.