Suspicious SearchIndexer Outbound Network Connection after Injection

ATT&CK techniques

Priv Esc → C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1055.012Process Hollowing
Defense Evasion
- T1055.012Process Hollowing
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.001Web Protocols
Exfiltration
Impact

What it detects

This rule detects the Windows SearchIndexer process making outbound network connections to non local addresses. SolarMarker StellarInjector injects the SolarPhantom backdoor into SearchIndexer to run hVNC and stealer traffic from a trusted host. SearchIndexer should not initiate internet connections so this indicates code injection and C2.

Reporting behind it

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Suspicious SearchIndexer Outbound Network Connection after Injection

Pivot detection · T1071.001 · 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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