From 0fc78b3c3b4d00d3f4d6e5aac18112e2c65dcba3 Mon Sep 17 00:00:00 2001
From: Brent Murphy <56412096+bm11100@users.noreply.github.com>
Date: Fri, 4 Sep 2020 11:30:01 -0400
Subject: [PATCH] [New Rule] Azure Key Vault Modified (#230)

* [New Rule] Azure Update to Key Vault

* Update rules/azure/credential_access_key_vault_update.toml

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

* Update credential_access_key_vault_modified.toml

Co-authored-by: Justin Ibarra <brokensound77@users.noreply.github.com>
---
 .../credential_access_key_vault_modified.toml | 54 +++++++++++++++++++
 1 file changed, 54 insertions(+)
 create mode 100644 rules/azure/credential_access_key_vault_modified.toml

diff --git a/rules/azure/credential_access_key_vault_modified.toml b/rules/azure/credential_access_key_vault_modified.toml
new file mode 100644
index 000000000..f52eb249c
--- /dev/null
+++ b/rules/azure/credential_access_key_vault_modified.toml
@@ -0,0 +1,54 @@
+[metadata]
+creation_date = "2020/08/31"
+ecs_version = ["1.6.0"]
+maturity = "production"
+updated_date = "2020/08/31"
+
+[rule]
+author = ["Elastic"]
+description = """
+Identifies modifications to a Key Vault in Azure. The Key Vault is a service that safeguards encryption keys and secrets
+like certificates, connection strings, and passwords. Because this data is sensitive and business critical, access to
+key vaults should be secured to allow only authorized applications and users.
+"""
+false_positives = [
+    """
+    Key vault modifications may be done by a system or network administrator. Verify whether the username, hostname,
+    and/or resource name should be making changes in your environment. Key vault modifications from unfamiliar users or
+    hosts should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
+    """,
+]
+from = "now-25m"
+index = ["filebeat-*"]
+language = "kuery"
+license = "Elastic License"
+name = "Azure Key Vault Modified"
+note = "The Azure Filebeat module must be enabled to use this rule."
+references = [
+    "https://docs.microsoft.com/en-us/azure/key-vault/general/basic-concepts",
+    "https://docs.microsoft.com/en-us/azure/key-vault/general/secure-your-key-vault",
+]
+risk_score = 47
+rule_id = "792dd7a6-7e00-4a0a-8a9a-a7c24720b5ec"
+severity = "medium"
+tags = ["Elastic", "Azure", "SecOps", "Continuous Monitoring", "Data Protection"]
+type = "query"
+
+query = '''
+event.module:azure and event.dataset:azure.activitylogs and event.category:Administrative and azure.activitylogs.operation_name:MICROSOFT.KEYVAULT/VAULTS/WRITE and event.outcome:Success
+'''
+
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1081"
+name = "Credentials in Files"
+reference = "https://attack.mitre.org/techniques/T1081/"
+
+
+[rule.threat.tactic]
+id = "TA0006"
+name = "Credential Access"
+reference = "https://attack.mitre.org/tactics/TA0006/"
+