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Initial Access via File Upload Followed by GET Request

This rule detects potential initial access activity where an adversary uploads a web shell or malicious script to a web server via a file upload mechanism (e.g., through a web form using multipart/form-data),…

Description

This rule detects potential initial access activity where an adversary uploads a web shell or malicious script to a web server via a file upload mechanism (e.g., through a web form using multipart/form-data), followed by a GET or POST request to access the uploaded file. By checking the body content of HTTP requests for file upload indicators such as "Content-Disposition: form-data" and "filename=", the rule identifies suspicious upload activities. This sequence of actions is commonly used by attackers to gain and maintain access to compromised web servers.

Detection logic

Its licence does not clear it for publishing here

Sunturai publishes a detection's own text where the licence it arrived under has been reviewed and permits it, and Elastic License 2.0 has not. The query as its source wrote it, its canonical form and the hash that pins this revision are in the workspace record.

Detection requirements

Platform
ContainersESXiIaaSLinuxmacOSNetwork DevicesWindows

The rule states no platform. This is derived from the 3 ATT&CK techniques it maps to.

Log source category
event_index

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