Detectionhightest

HackTool - EfsPotato Named Pipe Creation

Detects the pattern of a pipe name as used by the hack tool EfsPotato

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Launch

Florian Roth (Nextron Systems)Created Mon Aug 23Updated Thu Dec 21637f689e-b4a5-4a86-be0e-0100a0a33ba2windows

Log Source

WindowsNamed Pipe Created

ProductWindows← raw: windows

CategoryNamed Pipe Created← raw: pipe_created

Definition

Note that you have to configure logging for Named Pipe Events in Sysmon config (Event ID 17 and Event ID 18). The basic configuration is in popular sysmon configuration (https://github.com/SwiftOnSecurity/sysmon-config), but it is worth verifying. You can also use other repo, e.g. https://github.com/Neo23x0/sysmon-config, https://github.com/olafhartong/sysmon-modular. How to test detection? You can check powershell script from this site https://svch0st.medium.com/guide-to-named-pipes-and-hunting-for-cobalt-strike-pipes-dc46b2c5f575

Detection Logic

detection:
    selection:
        PipeName|contains:
            - '\pipe\'
            - '\pipe\srvsvc'  # more specific version (use only this one if the other causes too many false positives)
    filter_optional_ctx:
        PipeName|contains: '\CtxShare'
    filter_optional_default:
        PipeName|startswith: '\pipe\' # excludes pipes that start with \pipe\*
    condition: selection and not 1 of filter_optional_*