Web Shell Written to ScreenConnect App_Extensions Directory
- Product
- windows
- Category
- file_event
- Author
- HuntRule
- Published
- 2026-06-28
- Updated
- 2026-08-28
ATT&CK techniques
Initial Access → 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 aspx or ashx files written to the ScreenConnect App_Extensions directory, where post-exploitation of the authentication bypass drops server-side web shells for code execution. Huntress observed operators writing extension pages to this root after gaining admin access. Executable web content in this location is not part of normal product operation and signals web shell installation.
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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