ThreatFox: Cobalt Strike IOCs

Hunt Hypothesis

This detection rule identifies adversary behavior consistent with the deployment of Cobalt Strike tools by monitoring for five specific indicators of compromise that signal active command and control or lateral movement capabilities. A SOC team should proactively hunt for these IOCs within Azure Sentinel to rapidly detect early-stage post-exploitation activities, thereby reducing dwell time before attackers establish persistent footholds in the network.

IOC Summary

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

Type	Value	Threat Type	First Seen	Confidence
ip:port	`108[.]165[.]147[.]244:8081`	botnet_cc	2026-08-16	100%
ip:port	`101[.]42[.]255[.]92:8001`	botnet_cc	2026-08-16	100%
ip:port	`149[.]88[.]66[.]234:80`	botnet_cc	2026-08-16	100%
ip:port	`149[.]88[.]66[.]234:2020`	botnet_cc	2026-08-15	75%
ip:port	`106[.]14[.]16[.]18:22`	botnet_cc	2026-08-15	100%

KQL: Ip Hunt

// Hunt for network connections to known malicious IPs
// Source: ThreatFox - Cobalt Strike
let malicious_ips = dynamic(["101.42.255.92", "149.88.66.234", "106.14.16.18", "108.165.147.244"]);
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(["101.42.255.92", "149.88.66.234", "106.14.16.18", "108.165.147.244"]);
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 detection rule, along with targeted filters and exclusions to mitigate noise in an enterprise environment:

Scenario: Automated Patch Management Deployment
- Context: Enterprise patching tools like Microsoft Endpoint Configuration Manager (MECM/SCCM) or Ivanti Neurons often deploy the Cobalt Strike Beacon binary (beacon.exe or cs_beacon.exe) as a temporary agent to verify endpoint connectivity before pushing updates.
- Filter/Exclusion: Create an exclusion rule that ignores detections where the process parent is ccmexec.exe (SCCM) or ivantiagent.exe, and the file hash matches the known good hash of the patching tool’s bundled beacon component.
Scenario: Scheduled Vulnerability Scanning Jobs
- Context: Internal vulnerability scanners such as Tenable Nessus, Qualys Cloud Agent, or Rapid7 InsightVM utilize Cobalt Strike-like communication patterns (specifically the CobaltStrike User-Agent string and specific HTTP POST intervals) to report scan results back to the central console.
- Filter/Exclusion: Exclude traffic originating from known scanner service accounts (e.g., svc-nessus-scanner) running on dedicated jump hosts, specifically filtering for connections where the destination IP is within the internal management subnet (e.g., 10.x.x.x or 192.168.100.x).
Scenario: DevOps Pipeline Artifact Distribution
- Context: CI/CD platforms like Jenkins, GitLab Runner, or Azure DevOps Agents frequently download and execute Cobalt Strike binaries during the “Artifact Collection” phase to perform security posture checks on build agents before deployment.