Detectionhightest

Suspicious GrpConv Execution

Detects the suspicious execution of a utility to convert Windows 3.x .grp files or for persistence purposes by malicious software or actors

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Florian Roth (Nextron Systems)Created Thu May 19f14e169e-9978-4c69-acb3-1cff8200bc36windows

Log Source

WindowsProcess Creation

ProductWindows← raw: windows

CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic

detection:
    selection:
        CommandLine|contains:
            - 'grpconv.exe -o'
            - 'grpconv -o'
    condition: selection

False Positives

Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

References

MITRE ATT&CK

Tactics

Techniques

Rule Metadata

Rule ID

f14e169e-9978-4c69-acb3-1cff8200bc36

Status

test

Level

high

Type

Detection

Created

Thu May 19

Author

Path

rules/windows/process_creation/proc_creation_win_lolbin_susp_grpconv.yml

Raw Tags

attack.privilege-escalationattack.persistenceattack.t1547