From 02ee8195abc7a7326f9fb6abe6d97e1d4346515e Mon Sep 17 00:00:00 2001
From: Brent Murphy <56412096+bm11100@users.noreply.github.com>
Date: Mon, 8 Feb 2021 10:01:59 -0500
Subject: [PATCH] [New Rule] Creation or Modification of Root Certificate
 (#927)

* Create defense_evasion_create_mod_root_certificate.toml

* update description

* Update defense_evasion_create_mod_root_certificate.toml

* spacing

* Update rules/windows/defense_evasion_create_mod_root_certificate.toml

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

* removing process names that could lead to fn

Co-authored-by: Justin Ibarra <brokensound77@users.noreply.github.com>
---
 ...e_evasion_create_mod_root_certificate.toml | 57 +++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 rules/windows/defense_evasion_create_mod_root_certificate.toml

diff --git a/rules/windows/defense_evasion_create_mod_root_certificate.toml b/rules/windows/defense_evasion_create_mod_root_certificate.toml
new file mode 100644
index 000000000..ec43ec64a
--- /dev/null
+++ b/rules/windows/defense_evasion_create_mod_root_certificate.toml
@@ -0,0 +1,57 @@
+[metadata]
+creation_date = "2021/02/01"
+maturity = "production"
+updated_date = "2021/02/01"
+
+[rule]
+author = ["Elastic"]
+description = """
+Identifies the creation or modification of a local trusted root certificate in Windows. The install of a malicious root
+certificate would allow an attacker the ability to masquerade malicious files as valid signed components from any entity
+(e.g. Microsoft). It could also allow an attacker to decrypt SSL traffic.
+"""
+false_positives = ["Certain applications may install root certificates for the purpose of inspecting SSL traffic."]
+from = "now-9m"
+index = ["winlogbeat-*", "logs-endpoint.events.*", "logs-windows.*"]
+language = "eql"
+license = "Elastic License"
+name = "Creation or Modification of Root Certificate"
+references = [
+    "https://posts.specterops.io/code-signing-certificate-cloning-attacks-and-defenses-6f98657fc6ec",
+    "https://www.ired.team/offensive-security/persistence/t1130-install-root-certificate",
+]
+risk_score = 21
+rule_id = "203ab79b-239b-4aa5-8e54-fc50623ee8e4"
+severity = "low"
+tags = ["Elastic", "Host", "Windows", "Threat Detection", "Defense Evasion"]
+type = "eql"
+
+query = '''
+registry where event.type in ("creation", "change") and
+  registry.path :
+    (
+      "HKLM\\Software\\Microsoft\\SystemCertificates\\Root\\Certificates\\*\\Blob",
+      "HKLM\\Software\\Microsoft\\SystemCertificates\\AuthRoot\\Certificates\\*\\Blob",
+      "HKLM\\Software\\Policies\\Microsoft\\SystemCertificates\\Root\\Certificates\\*\\Blob",
+      "HKLM\\Software\\Policies\\Microsoft\\SystemCertificates\\AuthRoot\\Certificates\\*\\Blob"
+    )
+'''
+
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1553"
+name = "Subvert Trust Controls"
+reference = "https://attack.mitre.org/techniques/T1553/"
+[[rule.threat.technique.subtechnique]]
+id = "T1553.004"
+name = "Install Root Certificate"
+reference = "https://attack.mitre.org/techniques/T1553/004/"
+
+
+
+[rule.threat.tactic]
+id = "TA0005"
+name = "Defense Evasion"
+reference = "https://attack.mitre.org/tactics/TA0005/"