Mika Ayenson
63 lines
1.8 KiB
Python
63 lines
1.8 KiB
Python
# Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
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# or more contributor license agreements. Licensed under the Elastic License
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# 2.0; you may not use this file except in compliance with the Elastic License
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# 2.0.
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from . import common
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from . import RtaMetadata
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metadata = RtaMetadata(
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uuid="42eed432-af05-45d3-b788-7e3220f81f9a",
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platforms=["windows"],
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endpoint=[
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{
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"rule_name": "Suspicious ImageLoad via Windows Update Auto Update Client",
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"rule_id": "3788c03d-28a5-4466-b157-d6dd4dc449bb",
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}
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],
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siem=[],
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techniques=["T1218"],
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)
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EXE_FILE = common.get_path("bin", "renamed_posh.exe")
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PS1_FILE = common.get_path("bin", "Invoke-ImageLoad.ps1")
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RENAMER = common.get_path("bin", "rcedit-x64.exe")
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@common.requires_os(metadata.platforms)
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def main():
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wuauclt = "C:\\Users\\Public\\wuauclt.exe"
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user32 = "C:\\Windows\\System32\\user32.dll"
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dll = "C:\\Users\\Public\\unsigned.dll"
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ps1 = "C:\\Users\\Public\\Invoke-ImageLoad.ps1"
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rcedit = "C:\\Users\\Public\\rcedit.exe"
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common.copy_file(EXE_FILE, wuauclt)
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common.copy_file(user32, dll)
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common.copy_file(PS1_FILE, ps1)
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common.copy_file(RENAMER, rcedit)
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# Modify the originalfilename to invalidate the code sig
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common.log("Modifying the OriginalFileName attribute")
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common.execute([rcedit, dll, "--set-version-string", "OriginalFilename", "unsigned.exe"])
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common.log("Loading unsigned.dll into fake wuauclt")
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common.execute(
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[
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wuauclt,
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"-c",
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f"Import-Module {ps1}; Invoke-ImageLoad {dll}",
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";echo",
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"/RunHandlerComServer",
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";echo",
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"/UpdateDeploymentProvider",
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],
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timeout=10,
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)
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common.remove_files(wuauclt, dll, ps1, rcedit)
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if __name__ == "__main__":
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exit(main())
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