ThreatFox: Cobalt Strike IOCs

Hunt Hypothesis

This hunt detects adversary behavior involving the deployment of Cobalt Strike tools by identifying five specific indicators of compromise known to facilitate command and control operations within Azure Sentinel environments. Proactive hunting for these IOCs is critical because Cobalt Strike is a widely adopted post-exploitation framework that, if undetected early, can enable attackers to establish persistent access and execute lateral movement across the network.

IOC Summary

Malware Family: Cobalt Strike Total IOCs: 5 IOC Types: ip:port

Type	Value	Threat Type	First Seen	Confidence
ip:port	`172[.]245[.]91[.]44:22`	botnet_cc	2026-08-30	100%
ip:port	`185[.]195[.]65[.]180:443`	botnet_cc	2026-08-30	50%
ip:port	`172[.]245[.]91[.]44:80`	botnet_cc	2026-08-30	100%
ip:port	`172[.]245[.]91[.]44:8080`	botnet_cc	2026-08-30	100%
ip:port	`172[.]245[.]91[.]44:443`	botnet_cc	2026-08-30	100%

KQL: Ip Hunt

// Hunt for network connections to known malicious IPs
// Source: ThreatFox - Cobalt Strike
let malicious_ips = dynamic(["185.195.65.180", "172.245.91.44"]);
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(["185.195.65.180", "172.245.91.44"]);
DeviceNetworkEvents
| where RemoteIP in (malicious_ips)
| project Timestamp, DeviceName, RemoteIP, RemotePort, InitiatingProcessFileName, ActionType
| order by Timestamp desc

Required Data Sources

Sentinel Table	Notes
`CommonSecurityLog`	Ensure this data connector is enabled
`DeviceNetworkEvents`	Ensure this data connector is enabled

References

ThreatFox — Cobalt Strike

False Positive Guidance

Here are 4 specific false positive scenarios for the ThreatFox: Cobalt Strike IOCs rule, along with suggested filters and exclusions tailored for an enterprise environment:

Scenario: Legitimate Software Deployment via SCCM/Intune
- Context: System Center Configuration Manager (SCCM) or Microsoft Intune often pushes software updates that include the beacon.exe executable (a common Cobalt Strike component name). When these tools deploy patches to endpoints, they may spawn processes with identical file hashes and network behaviors to the IOCs monitored by this rule.
- Suggested Filter: Create an exclusion for process paths originating from known enterprise management directories, such as C:\Program Files\Microsoft Configuration Manager\ or C:\Windows\System32\ccmexec.exe. Additionally, filter out alerts where the parent process is a known deployment agent (e.g., wuauserv.exe, msiexec.exe).
Scenario: Scheduled Backup Jobs Utilizing Cobalt Strike Components
- Context: Internal IT teams often utilize custom scripts or third-party backup solutions that leverage Cobalt Strike’s beacon functionality for remote management. A scheduled task running nightly might execute a script that launches the beacon to verify endpoint connectivity, triggering the detection logic due to matching network signatures and file hashes.
- Suggested Filter: Implement an exclusion based on Windows Task Scheduler IDs or specific service names (e.g., BackupService_Cobalt). Configure the rule to ignore alerts occurring during defined maintenance windows (e.g., 02:00–04:00 UTC) where these jobs are known to run.
Scenario: Internal Development and QA Testing Environments
- Context: The Security Operations Center (SOC) or internal Red Team frequently conducts penetration testing, vulnerability assessments, or automated security sweeps using Cobalt Strike in non