Possible Pre-Auth Webshell Upload via Oracle Opera FileReceiver Servlet

ATT&CK techniques

Initial Access → Persistence

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
Persistence
- T1505.003Web Shell
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects HTTP requests to the Oracle Opera FileReceiver servlet used to drop a CGI webshell into the operabin cgi-bin directory. Assetnote research chains an order-of-operations bug to reach pre-auth remote code execution via this servlet, which attackers use to plant a webshell for persistent command execution.

Reporting behind it

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Possible Pre-Auth Webshell Upload via Oracle Opera FileReceiver Servlet

Pivot detection · T1190 · 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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