From 538aa80bba56535bb32eaab6cad9ef44d959ea30 Mon Sep 17 00:00:00 2001
From: Samirbous <64742097+Samirbous@users.noreply.github.com>
Date: Tue, 8 Dec 2020 22:26:11 +0100
Subject: [PATCH] [New Rule] Process Termination Followed by Deletion (#482)

* [New Rule] Process Termination Followed by Deletion

* excluded SoftwareDistrib and WinSxS Folders

* added drive letter for better performance

* excluded signed PE

* eql syntax

* ecs_version

* Update rules/windows/defense_evasion_process_termination_followed_by_deletion.toml

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

* Update rules/windows/defense_evasion_process_termination_followed_by_deletion.toml

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

* Update rules/windows/defense_evasion_process_termination_followed_by_deletion.toml

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

* Update rules/windows/defense_evasion_process_termination_followed_by_deletion.toml

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

* added few more extension as suggested by DanStep

* dropped winlogbeat due to pe.codesign

Co-authored-by: Brent Murphy <56412096+bm11100@users.noreply.github.com>
Co-authored-by: David French <56409778+threat-punter@users.noreply.github.com>
Co-authored-by: Justin Ibarra <brokensound77@users.noreply.github.com>
---
 ...cess_termination_followed_by_deletion.toml | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)
 create mode 100644 rules/windows/defense_evasion_process_termination_followed_by_deletion.toml

diff --git a/rules/windows/defense_evasion_process_termination_followed_by_deletion.toml b/rules/windows/defense_evasion_process_termination_followed_by_deletion.toml
new file mode 100644
index 000000000..b6fd1d61e
--- /dev/null
+++ b/rules/windows/defense_evasion_process_termination_followed_by_deletion.toml
@@ -0,0 +1,45 @@
+[metadata]
+creation_date = "2020/11/04"
+maturity = "production"
+updated_date = "2020/11/04"
+
+[rule]
+author = ["Elastic"]
+description = """
+Identifies a process termination event quickly followed by the deletion of its executable file. Malware tools and other non-native
+files dropped or created on a system by an adversary may leave traces to indicate to what occurred. Removal of these files can occur during an intrusion, or as part of a post-intrusion process to minimize the
+adversary's footprint.
+"""
+from = "now-9m"
+index = ["logs-endpoint.events.*"]
+language = "eql"
+license = "Elastic License"
+name = "Process Termination followed by Deletion"
+risk_score = 47
+rule_id = "09443c92-46b3-45a4-8f25-383b028b258d"
+severity = "medium"
+tags = ["Elastic", "Host", "Windows", "Threat Detection", "Defense Evasion"]
+type = "eql"
+
+query = '''
+sequence by host.id with maxspan=5s
+   [process where event.type == "end" and 
+    process.code_signature.trusted == false and
+    not process.executable : ("C:\\Windows\\SoftwareDistribution\\*.exe", "C:\\Windows\\WinSxS\\*.exe")
+   ] by process.executable
+   [file where event.type == "deletion" and file.extension : ("exe", "scr", "com")] by file.path
+'''
+
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1070"
+name = "Indicator Removal on Host"
+reference = "https://attack.mitre.org/techniques/T1070/"
+
+
+[rule.threat.tactic]
+id = "TA0005"
+name = "Defense Evasion"
+reference = "https://attack.mitre.org/tactics/TA0005/"