Suspicious XScan Network Vulnerability Scanner Execution After Citrix Bleed Exploitation

ATT&CK techniques

Discovery

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
- T1046Network Service Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects execution of the XScan network scanner with finger and vulnerability scanning flags against a subnet, matching internal reconnaissance seen after Citrix Bleed exploitation by Unit 42. Adversaries sweep the environment for hosts and weaknesses which precedes lateral movement and marks an active operator on the network.

Reporting behind it

Related detections9 linkedT1046 — drag to rearrange

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Suspicious SoftPerfect Network Scanner Execution for Discovery

Suspicious SoftPerfect Network Scanner Execution (via process_creation)

Suspicious XScan Network Vulnerability Scanner Execution After Citrix Bleed Exploitation

Pivot detection · T1046 · 9 related

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

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