Find sigma rule 
Attack: Hide Artifacts
Adversaries may attempt to hide artifacts associated with their behaviors to evade detection. Operating systems may have features to hide various artifacts, such as important system files and administrative task execution, to avoid disrupting user work environments and prevent users from changing files or features on the system. Adversaries may abuse these features to hide artifacts such as files, directories, user accounts, or other system activity to evade detection.(Citation: Sofacy Komplex Trojan)(Citation: Cybereason OSX Pirrit)(Citation: MalwareBytes ADS July 2015)
Adversaries may also attempt to hide artifacts associated with malicious behavior by creating computing regions that are isolated from common security instrumentation, such as through the use of virtualization technology.(Citation: Sophos Ragnar May 2020)
MITRE
Tactic
- defense-evasion
technique
- T1564
Test : Extract binary files via VBA
OS
- windows
Description:
This module extracts a binary (calc.exe) from inside of another binary.
In the wild maldoc authors will use this technique to hide binaries inside of files stored within the office document itself. An example of this technique can be seen in sample
f986040c7dd75b012e7dfd876acb33a158abf651033563ab068800f07f508226
This sample contains a document inside of itself. Document 1 is the actual maldoc itself, document 2 is the same document without all the malicious code. Document 1 will copy Document 2 to the file system and then “peek” inside of this document and pull out the oleObject.bin file. Contained inside of this oleObject.bin file is a payload that is parsed out and executed on the file system.
Executor
powershell
Sigma Rule
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registry_set_office_trust_record_susp_location.yml (id: a166f74e-bf44-409d-b9ba-ea4b2dd8b3cd)
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image_load_office_vbadll_load.yml (id: e6ce8457-68b1-485b-9bdd-3c2b5d679aa9)
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net_connection_win_susp_file_sharing_domains_susp_folders.yml (id: e0f8ab85-0ac9-423b-a73a-81b3c7b1aa97)
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net_connection_win_powershell_network_connection.yml (id: 1f21ec3f-810d-4b0e-8045-322202e22b4b)
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file_event_win_office_susp_file_extension.yml (id: c7a74c80-ba5a-486e-9974-ab9e682bc5e4)
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proc_creation_win_office_spawn_exe_from_users_directory.yml (id: aa3a6f94-890e-4e22-b634-ffdfd54792cc)
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image_load_dll_dbghelp_dbgcore_susp_load.yml (id: 0e277796-5f23-4e49-a490-483131d4f6e1)