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

Related detections9 linkedT1071.001 — drag to rearrange

Suspicious AppLaunch.exe Spawned As Injection Target (via process_creation)

Possible Remcos C2 Connection from eilowutil Process

Possible MOVEit Transfer SSRF via MOVEitISAPI action m2

Suspicious Tomcat Campaign Command and Control Domain Resolution (via dns_query)

Suspicious TeamTNT Command and Control Domain Resolution (via dns_query)

Malicious CastleLoader C2 Communication via Hardcoded User-Agent

Suspicious JScript.NET Compiler Spawned by AutoIt for Process Hollowing

Suspicious Outbound Connection From CasPol Binary

Suspicious Cobalt Strike Loader C2 Traffic via Forged MSIE yie9 User-Agent (via proxy)

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.

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 →