Malicious XCSSET Payload Drop to Temp and Hidden Home Paths

ATT&CK techniques

Persistence → Priv Esc

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1543.001Launch Agent
Priv Esc
- T1543.001Launch Agent
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects creation of the specific staging artifacts used by XCSSET v4.0 including the tmp p.app bundle the tmp r file and the hidden tr file in the user home directory. These fixed drop paths hold the malware components and persistence loaders. Detecting these file writes provides a strong campaign-specific indicator of an XCSSET infection.

Reporting behind it

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Malicious XCSSET Payload Drop to Temp and Hidden Home Paths

Pivot detection · T1543.001 · 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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