Suspicious ASPX Webshell Written to IIS inetsrv Directory via file_event
- Product
- windows
- Category
- file_event
- Author
- HuntRule
- Published
- 2026-07-03
- Updated
- 2026-08-28
ATT&CK techniques
PersistenceRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects an fd.aspx file being written under the IIS inetsrv directory, matching the webshell dropped by the hacktivist actors for server access. Web-facing script files appearing in the IIS binaries path are a hallmark of server-side webshell deployment. This supports persistence and remote command execution on internet-facing hosts.
Reporting behind it
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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Also included
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