Suspicious Remote Access Tool User Agent in Outbound Traffic via Proxy

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
- T1219Remote Access Tools
Exfiltration
Impact

What it detects

This rule detects outbound HTTP requests carrying the NetSupport Manager or JWrapperDownloader user agents, network fingerprints of remote access tooling used during intrusions. Because these agents accompany download and command-and-control traffic for tools frequently abused as RATs, their presence in proxy logs indicates remote access tool activity that should be validated against sanctioned software.

Reporting behind it

Related detections9 linkedT1105 — drag to rearrange

Malicious CrowdStrike Falcon RTR Abuse Downloading From fleetdeck.io by UNC3944 (via process_creation)

Suspicious Curl Download to Update Executable during FortiClient EMS Exploitation

Suspicious Velociraptor Agent Deployment via msiexec From Cloud Storage

Suspicious node.exe or code.exe Execution from Public Music Directory

Suspicious File Creation by OpenEDR ITSMService on Windows

Windows: TacticalRMM Agent Installed with API/Auth Flags Pointing to Remote RMM Server

Malicious PowerShell In-Memory Download Cradle via Script Block (via ps_script)

Suspicious Atera Agent Silent Onboarding via Process Creation

Malicious Hidden Virtual Machine Launched via QEMU for Persistence

Suspicious Remote Access Tool User Agent in Outbound Traffic via Proxy

Pivot detection · T1105 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

Full detection rule

Unlock this rule to view and copy it

The detection logic is included with a plan. Everything else — context, mappings and implementation details — stays free on this page.

Sign in for 3 free unlocks

Signing in gives you 3 unlocks to spend on any rule in the library. No card, and they do not expire.

Also included

Unlocked rules convert on this page — to Splunk SPL or Splunk — Raw Index SPL or Microsoft Sentinel KQL or Microsoft Sentinel ASIM ASIM KQL or Microsoft Defender XDR KQL or Elastic Security KQL or Elastic Security Lucene or Elastic Security ES|QL or CrowdStrike Falcon CQL or SentinelOne PowerQuery or Palo Alto Cortex XDR XQL or Carbon Black Cloud Platform Search or Carbon Black EDR Process Search or Google Security Operations UDM Search or IBM QRadar AQL or Sumo Logic Cloud SIEM Rules expression or Rapid7 InsightIDR LEQL or Graylog Search or OpenSearch Lucene or OpenSearch PPL PPL or Grafana Loki LogQL or SQLite SQL or Zircolite SQLite — with the log-source profile the engine picked, the field map it used, and everything it could not express. Converting a rule you have unlocked costs no further credit.

See it run on a free rule →Convert your own rule →