Suspicious Process Execution From Fake Microsoft Edge ExtSvc Directory

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1036.005Match Legitimate Resource Name or Location
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a process running from a %LOCALAPPDATA%\Microsoft\Edge\ExtSvc directory, a fake path that impersonates the Microsoft Edge browser folder. The CrystalX RAT installs itself under this masquerading Edge subfolder to blend with legitimate browser files as reported by Kaspersky. Execution from this non-existent Edge location indicates the spyware and stealer establishing a hidden foothold.

Reporting behind it

Related detections9 linkedT1036.005 — drag to rearrange

Suspicious kswapd0 Masquerading Miner Process

Suspicious msinfo32.exe Executed From ViPNet Update Directory

Malicious Desktop Window Manager Impersonation From Non-System Path via process_creation

Malicious Svchost Impersonation From Non-System Path via process_creation

Malicious RustyStealer Masquerading as AudioDriver in Windows Temp

Suspicious svchost Invocation with Non-Standard svcr Argument

Suspicious Scheduled Task Masquerading as Microsoft Edge Update Machine MS

Malicious Netcat Reverse Shell via Masqueraded StartMenuExperienceHost

Suspicious Head Mare srvhost.exe Masquerading as System Service Host

Suspicious Process Execution From Fake Microsoft Edge ExtSvc Directory

Pivot detection · T1036.005 · 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 →