Detectionmediumtest

Assembly DLL Creation Via AspNetCompiler

Detects the creation of new DLL assembly files by "aspnet_compiler.exe", which could be a sign of "aspnet_compiler" abuse to proxy execution through a build provider.

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Launch
Nasreddine Bencherchali (Nextron Systems)Created Mon Aug 144c7f49ee-2638-43bb-b85b-ce676c30b260windows
Log Source
WindowsFile Event
ProductWindows← raw: windows
CategoryFile Event← raw: file_event

Events for file system activity including creation, modification, and deletion.

Detection Logic
Detection Logic1 selector
detection:
    selection:
        Image|endswith: '\aspnet_compiler.exe'
        TargetFilename|contains|all:
            - '\Temporary ASP.NET Files\'
            - '\assembly\tmp\'
            - '.dll'
    condition: selection
False Positives

Legitimate assembly compilation using a build provider

References
1
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Internal Research