ThreatFox: XWorm IOCs

Hunt Hypothesis

This hunt targets known indicators of compromise associated with XWorm, a ransomware strain that typically leverages initial access vectors to deploy malicious payloads and encrypt critical data. Proactively hunting for these IOCs in Azure Sentinel allows the SOC team to identify and isolate compromised endpoints before the ransomware can propagate laterally or execute its encryption routine.

IOC Summary

Malware Family: XWorm Total IOCs: 2 IOC Types: ip:port

KQL: Ip Hunt

// Hunt for network connections to known malicious IPs
// Source: ThreatFox - XWorm
let malicious_ips = dynamic(["82.47.101.153", "188.52.56.123"]);
CommonSecurityLog
| where DestinationIP in (malicious_ips) or SourceIP in (malicious_ips)
| project TimeGenerated, SourceIP, DestinationIP, DestinationPort, DeviceAction, Activity
| order by TimeGenerated desc

KQL: Ip Hunt Device

// Hunt in Defender for Endpoint network events
let malicious_ips = dynamic(["82.47.101.153", "188.52.56.123"]);
DeviceNetworkEvents
| where RemoteIP in (malicious_ips)
| project Timestamp, DeviceName, RemoteIP, RemotePort, InitiatingProcessFileName, ActionType
| order by Timestamp desc

Required Data Sources

References

• ThreatFox — XWorm

False Positive Guidance

• Scenario: A DevOps engineer uses a CI/CD pipeline (e.g., Jenkins or GitHub Actions) to deploy a microservice that includes a binary or configuration file matching one of the XWorm IOCs (e.g., a specific SHA256 hash or file path) as part of a standard build artifact.
  • Filter/Exclusion: Exclude alerts where the source process is a known CI/CD agent (e.g., jenkins.exe, agent.exe, docker.exe) or where the parent process is a build tool (e.g., msbuild.exe, gradle.exe).
• Scenario: An IT administrator performs a manual software update or patch deployment using a tool like SCCM (System Center Configuration Manager) or PDQ Deploy, which temporarily writes a known installer package to a temporary directory that matches the IOC path or hash.
  • Filter/Exclusion: Exclude events where the parent process is a deployment agent (e.g., ccmexec.exe, pdqdeploy.exe) or where the file location is within standard temporary directories (%TEMP%, C:\Windows\Temp) and the process chain includes a service host (svchost.exe) with a known deployment service.
• Scenario: A security team runs a YARA rule scan or memory dump analysis using tools like Volatility or YARA Scanner, which may load or reference the IOC hashes/paths as part of the scanning process, triggering the detection logic if the rule matches on file access or process command-line arguments.
  • Filter/Exclusion: Exclude alerts where the source process is a known security tool (e.g., yara.exe, volatility.exe, wazuh-agent.exe) or where the command-line arguments contain keywords like --scan, --match, or yara.
• Scenario: A legacy application or third