Malicious Web Server Spawning Command Shell and curl Download via Webshell

ATT&CK techniques

Persistence → C2

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1505.003Web Shell
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects an Apache httpd web server process spawning a command shell or curl download, matching AntSword webshell activity in the Nezha China-nexus intrusion set. The webserver context is abused to execute commands and pull additional tooling onto the host. Legitimate web servers do not launch interactive shells or file downloaders, making this a strong webshell indicator.

Reporting behind it

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Malicious Web Server Spawning Command Shell and curl Download via Webshell

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.

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