From 9d884b6452f042bce0da96e7be2e0fb6289ceff5 Mon Sep 17 00:00:00 2001
From: Samirbous <64742097+Samirbous@users.noreply.github.com>
Date: Tue, 22 Sep 2020 22:39:35 +0200
Subject: [PATCH] [New Rule] Potential DLL SideLoading via Trusted Microsoft
 Programs (#253)

* [New Rule] Potential DLL SideLoading via Trusted Microsoft Programs

* Update rules/windows/defense_evasion_execution_suspicious_explorer_winword.toml

Co-authored-by: Brent Murphy <56412096+bm11100@users.noreply.github.com>

* Update rules/windows/defense_evasion_execution_suspicious_explorer_winword.toml

Co-authored-by: Justin Ibarra <brokensound77@users.noreply.github.com>

* Update defense_evasion_execution_suspicious_explorer_winword.toml

* Update defense_evasion_execution_suspicious_explorer_winword.toml

* Added 2 more known vulnerable programs Dism.exe and w3wp.exe

* Update defense_evasion_execution_suspicious_explorer_winword.toml

* linted

* Update rules/windows/defense_evasion_execution_suspicious_explorer_winword.toml

Co-authored-by: David French <56409778+threat-punter@users.noreply.github.com>

Co-authored-by: Brent Murphy <56412096+bm11100@users.noreply.github.com>
Co-authored-by: Justin Ibarra <brokensound77@users.noreply.github.com>
Co-authored-by: David French <56409778+threat-punter@users.noreply.github.com>
---
 ...execution_suspicious_explorer_winword.toml | 47 +++++++++++++++++++
 1 file changed, 47 insertions(+)
 create mode 100644 rules/windows/defense_evasion_execution_suspicious_explorer_winword.toml

diff --git a/rules/windows/defense_evasion_execution_suspicious_explorer_winword.toml b/rules/windows/defense_evasion_execution_suspicious_explorer_winword.toml
new file mode 100644
index 000000000..9c4178b3b
--- /dev/null
+++ b/rules/windows/defense_evasion_execution_suspicious_explorer_winword.toml
@@ -0,0 +1,47 @@
+[metadata]
+creation_date = "2020/09/03"
+ecs_version = ["1.6.0"]
+maturity = "production"
+updated_date = "2020/09/03"
+
+[rule]
+author = ["Elastic"]
+description = """
+Identifies an instance of a Windows trusted program that is known to be vulnerable to DLL Search Order Hijacking starting
+after being renamed or from a non-standard path. This is uncommon behavior and may indicate an attempt to evade defenses
+via side loading a malicious DLL within the memory space of one of those processes.
+"""
+from = "now-9m"
+index = ["winlogbeat-*", "logs-endpoint.events.*"]
+language = "kuery"
+license = "Elastic License"
+name = "Potential DLL SideLoading via Trusted Microsoft Programs"
+risk_score = 73
+rule_id = "1160dcdb-0a0a-4a79-91d8-9b84616edebd"
+severity = "high"
+tags = ["Elastic", "Windows"]
+type = "query"
+
+query = '''
+event.category:process and event.type:(start or process_started) and
+ process.pe.original_file_name:(WinWord.exe or EXPLORER.EXE or w3wp.exe or DISM.EXE) and
+ not (process.name:(winword.exe or WINWORD.EXE or explorer.exe or w3wp.exe or Dism.exe) or
+             process.executable:("C:\Windows\explorer.exe" or C\:\\Program?Files\\Microsoft?Office\\root\\Office*\\WINWORD.EXE or 
+                C\:\\Program?Files?\(x86\)\\Microsoft?Office\\root\\Office*\\WINWORD.EXE or 
+                 "C:\Windows\System32\Dism.exe" or "C:\Windows\SysWOW64\Dism.exe" or 
+                  "C:\Windows\System32\inetsrv\w3wp.exe"))
+'''
+
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1036"
+name = "Masquerading"
+reference = "https://attack.mitre.org/techniques/T1036/"
+
+
+[rule.threat.tactic]
+id = "TA0005"
+name = "Defense Evasion"
+reference = "https://attack.mitre.org/tactics/TA0005/"