THREAT-387 Sublime Security Rules

Pipfile

@@ -19,7 +19,7 @@ wrapt = "~=1.15"
 [packages]
 policyuniverse = "==1.5.1.20230817"
 requests = "==2.31.0"
-panther-analysis-tool = "~=0.52.2"
+panther-analysis-tool = "~=0.53.0"
 panther-detection-helpers = "==0.4.0"
 
 [requires]

global_helpers/panther_sublime_helpers.py

@@ -0,0 +1,10 @@
+def sublime_alert_context(event) -> dict:
+    context = {}
+    context["events_type"] = event.get("type", default="<TYPE_NOT_FOUND>")
+    context["users_emails"] = event.deep_get(
+        "created_by", "email_address", default="<EMAIL_NOT_FOUND>"
+    )
+    context["users_role"] = event.deep_get("created_by", "role", default="<ROLES_NOT_FOUND>")
+    context["request_ip"] = event.deep_get("data", "request", "ip", default="<IP_NOT_FOUND>")
+    context["request_path"] = event.deep_get("data", "request", "path", default="<PATH_NOT_FOUND>")
+    return context

global_helpers/panther_sublime_helpers.yml

@@ -0,0 +1,5 @@
+AnalysisType: global
+Filename: panther_sublime_helpers.py
+GlobalID: "panther_sublime_helpers"
+Description: >
+  Global helpers for Sublime detections

packs/sublime.yml

@@ -0,0 +1,12 @@
+AnalysisType: pack
+PackID: PantherManaged.Sublime
+Description: Group of all Sublime Security detections
+PackDefinition:
+  IDs:
+    - Sublime.Mailbox.Deactivated
+    - Sublime.Message.Flagged
+    - Sublime.Message.Source.Deleted.Or.Deactivated
+    - Sublime.Rules.Deleted.Or.Deactivated
+    # Globals used in these detections
+    - panther_sublime_helpers
+DisplayName: "Panther Sublime Pack"

rules/sublime_rules/sublime_mailboxes_deactivated.py

@@ -0,0 +1,9 @@
+from panther_sublime_helpers import sublime_alert_context
+
+
+def rule(event):
+    return event.get("type") == "message_source.deactivate_mailboxes"
+
+
+def alert_context(event):
+    return sublime_alert_context(event)

rules/sublime_rules/sublime_mailboxes_deactivated.yml

@@ -0,0 +1,84 @@
+AnalysisType: rule
+Description: A Sublime User disabled some mailbox(es).
+DisplayName: "Sublime Mailbox Deactivated"
+Enabled: true
+Filename: sublime_mailboxes_deactivated.py
+Runbook: Assess if this was done by the user for a valid business reason. Be vigilant to re-enable the mailboxes if it's in the best security interest for your organization's security posture.
+Reference: https://docs.sublime.security/docs/add-message-source
+Severity: Medium
+DedupPeriodMinutes: 60
+AlertTitle: Sublime message mailbox(es) were deactivated
+LogTypes:
+  - Sublime.Audit
+RuleID: "Sublime.Mailbox.Deactivated"
+Threshold: 1
+Reports:
+  MITRE ATT&CK:
+    - TA0005:T1562.001 # Impair Defenses: Disable or Modify Tools
+Tests:
+  - ExpectedResult: false
+    Name: Other Events
+    Log:
+      {
+        "created_at": "2024-09-09 19:33:34.237078000",
+        "created_by": {
+          "active": true,
+          "created_at": "2024-08-28 22:05:15.715644000",
+          "email_address": "[email protected]",
+          "first_name": "John",
+          "google_oauth_user_id": "",
+          "id": "cd3aedfe-a61f-4e0e-ba30-14dcc7883316",
+          "is_enrolled": true,
+          "last_name": "Doe",
+          "microsoft_oauth_user_id": "",
+          "role": "admin",
+          "updated_at": "2024-08-28 22:05:15.715644000"
+          },
+          "data": {
+            "request": {
+              "authentication_method": "user_session",
+              "body": "{\"mailbox_ids\":[\"493c6e21-7787-419b-bada-7c4f50cbb932\"]}",
+              "id": "73444211-31af-42d8-99b4-34a139cf7d4a",
+              "ip": "1.2.3.4",
+              "method": "POST",
+              "path": "/v1/message-sources/febb5bf4-2ead-47b1-b467-0ac729bf6871/deactivate",
+              "query": { },
+              "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36"
+              }
+            },
+            "id": "084732e5-7704-4bbe-ab5a-77f1aa65a737",
+            "type": "message_source.deactivate"
+        }
+  - ExpectedResult: true
+    Name: Mailbox Deactivated
+    Log:
+      {
+        "created_at": "2024-09-09 19:33:34.237078000",
+        "created_by": {
+          "active": true,
+          "created_at": "2024-08-28 22:05:15.715644000",
+          "email_address": "[email protected]",
+          "first_name": "John",
+          "google_oauth_user_id": "",
+          "id": "cd3aedfe-a61f-4e0e-ba30-14dcc7883316",
+          "is_enrolled": true,
+          "last_name": "Doe",
+          "microsoft_oauth_user_id": "",
+          "role": "admin",
+          "updated_at": "2024-08-28 22:05:15.715644000"
+          },
+          "data": {
+            "request": {
+              "authentication_method": "user_session",
+              "body": "{\"mailbox_ids\":[\"493c6e21-7787-419b-bada-7c4f50cbb932\"]}",
+              "id": "73444211-31af-42d8-99b4-34a139cf7d4a",
+              "ip": "1.2.3.4",
+              "method": "POST",
+              "path": "/v1/message-sources/febb5bf4-2ead-47b1-b467-0ac729bf6871/deactivate",
+              "query": { },
+              "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36"
+              }
+            },
+            "id": "084732e5-7704-4bbe-ab5a-77f1aa65a737",
+            "type": "message_source.deactivate_mailboxes"
+        }

rules/sublime_rules/sublime_message_flagged.py

@@ -0,0 +1,14 @@
+def rule(event):
+    return event.get("type") == "message.flagged"
+
+
+def alert_context(event):
+    flagged_rules = event.deep_walk("data", "flagged_rules", "name", default=["<UNKNOWN_NAMES>"])
+    return {
+        "flagged_rules": flagged_rules,
+    }
+
+
+def title(event):
+    rule_count = len(event.deep_get("data", "flagged_rules", default=[]))
+    return f"Sublime flagged email message that matched {rule_count} Sublime rules"

rules/sublime_rules/sublime_message_flagged.yml

@@ -0,0 +1,69 @@
+AnalysisType: rule
+Description: Sublime flagged some messages as suspicious.
+DisplayName: "Sublime Flagged an Email"
+Enabled: true
+Filename: sublime_message_flagged.py
+# Runbook: Assess if this was done by the user for a valid business reason. Be vigilant to re-enable the mailboxes if it's in the best security interest for your organization's security posture.
+# Reference: https://docs.sublime.security/docs/add-message-source
+Severity: High
+DedupPeriodMinutes: 60
+LogTypes:
+  - Sublime.MessageEvent
+RuleID: "Sublime.Message.Flagged"
+Threshold: 1
+Tests:
+  - ExpectedResult: true
+    Name: Message Flagged
+    Log:
+      {
+      	"p_source_file": {
+      		"aws_s3_bucket": "audit.log.export",
+      		"aws_s3_key": "sublime_platform_message_events/2024/09/24/164544Z-FPXIFG.json"
+      	},
+      	"p_any_sha256_hashes": [
+      		"fb8b46e3317ac7d5036c6b21517d363634293c6d4f6bf1b1e67548c80948a1c6"
+      	],
+      	"p_event_time": "2024-09-24 16:45:43.302769000",
+      	"p_log_type": "Sublime.MessageEvent",
+      	"p_parse_time": "2024-09-24 16:51:47.687095351",
+      	"p_row_id": "a23385494d57dfbbbdcbe4fa218101",
+      	"p_schema_version": 0,
+      	"p_source_id": "7e2a59aa-687e-430e-ae4a-81d3c0163f52",
+      	"p_source_label": "Sublime Real Logs",
+      	"p_udm": {},
+      	"created_at": "2024-09-24 16:45:43.302769000",
+      	"data": {
+      		"flagged_rules": [
+      			{
+      				"id": "b0ab266f-8a12-4020-b165-e97bb1aacc42",
+      				"name": "Credential phishing: Engaging language and other indicators (untrusted sender)"
+      			},
+      			{
+      				"id": "a014f82e-f2d7-4058-adb1-36fc086de0b8",
+      				"name": "Attachment: HTML smuggling with unescape"
+      			},
+      			{
+      				"id": "e4866908-60fe-46f0-866e-84d412627006",
+      				"name": "Headers: Zimbra mailer from a non-supported OS version"
+      			},
+      			{
+      				"id": "5a9dc2cd-39f5-4814-95df-aa7614cc8bdd",
+      				"name": "Impersonation: Human Resources with link or attachment and engaging language"
+      			},
+      			{
+      				"id": "7988f1f5-5c95-42c2-9140-ead5a975918e",
+      				"name": "Request for Quote or Purchase (RFQ|RFP) with HTML smuggling attachment"
+      			}
+      		],
+      		"message": {
+      			"canonical_id": "fb8b46e3317ac7d5036c6b21517d363634293c6d4f6bf1b1e67548c80948a1c6",
+      			"external_id": "b86b1e58-e9f8-4b55-8b54-1402f9f95e69",
+      			"id": "019224ec-aba6-763d-bb2e-cd4cbd40a29f",
+      			"mailbox": {
+      				"id": "624c8394-4fe2-4ba0-bd2b-86d2e503c614"
+      			},
+      			"message_source_id": "91956379-c2f3-4c50-a410-3ba89fb8bc74"
+      		}
+      	},
+      	"type": "message.flagged"
+      }

rules/sublime_rules/sublime_message_source_deleted_or_deactivated.py

@@ -0,0 +1,14 @@
+from panther_sublime_helpers import sublime_alert_context
+
+SUSPICIOUS_EVENTS = [
+    "message_source.deactivate",
+    "message_source.delete",
+]
+
+
+def rule(event):
+    return event.get("type") in SUSPICIOUS_EVENTS
+
+
+def alert_context(event):
+    return sublime_alert_context(event)

rules/sublime_rules/sublime_message_source_deleted_or_deactivated.yml

@@ -0,0 +1,84 @@
+AnalysisType: rule
+Description: A Sublime User disabled or deleted some message source(s).
+DisplayName: "Sublime Message Source Deleted Or Deactivated"
+Enabled: true
+Filename: sublime_message_source_deleted_or_deactivated.py
+Runbook: Assess if this was done by the user for a valid business reason. Be vigilant to re-enable the message source(s) if it's in the best security interest for your organization's security posture.
+Reference: https://docs.sublime.security/docs/message-types
+Severity: Medium
+DedupPeriodMinutes: 60
+AlertTitle: Sublime message source(s) were deleted or deactivated
+LogTypes:
+  - Sublime.Audit
+RuleID: "Sublime.Message.Source.Deleted.Or.Deactivated"
+Threshold: 1
+Reports:
+  MITRE ATT&CK:
+    - TA0005:T1562.001 # Impair Defenses: Disable or Modify Tools
+Tests:
+  - ExpectedResult: true
+    Name: Message Source Deactivated
+    Log:
+      {
+        "created_at": "2024-09-09 19:33:34.237078000",
+        "created_by": {
+          "active": true,
+          "created_at": "2024-08-28 22:05:15.715644000",
+          "email_address": "[email protected]",
+          "first_name": "John",
+          "google_oauth_user_id": "",
+          "id": "cd3aedfe-a61f-4e0e-ba30-14dcc7883316",
+          "is_enrolled": true,
+          "last_name": "Doe",
+          "microsoft_oauth_user_id": "",
+          "role": "admin",
+          "updated_at": "2024-08-28 22:05:15.715644000"
+          },
+          "data": {
+            "request": {
+              "authentication_method": "user_session",
+              "body": "{\"mailbox_ids\":[\"493c6e21-7787-419b-bada-7c4f50cbb932\"]}",
+              "id": "73444211-31af-42d8-99b4-34a139cf7d4a",
+              "ip": "1.2.3.4",
+              "method": "POST",
+              "path": "/v1/message-sources/febb5bf4-2ead-47b1-b467-0ac729bf6871/deactivate",
+              "query": { },
+              "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36"
+              }
+            },
+            "id": "084732e5-7704-4bbe-ab5a-77f1aa65a737",
+            "type": "message_source.deactivate"
+        }
+  - ExpectedResult: false
+    Name: Other Events
+    Log:
+      {
+        "created_at": "2024-09-09 19:33:34.237078000",
+        "created_by": {
+          "active": true,
+          "created_at": "2024-08-28 22:05:15.715644000",
+          "email_address": "[email protected]",
+          "first_name": "John",
+          "google_oauth_user_id": "",
+          "id": "cd3aedfe-a61f-4e0e-ba30-14dcc7883316",
+          "is_enrolled": true,
+          "last_name": "Doe",
+          "microsoft_oauth_user_id": "",
+          "role": "admin",
+          "updated_at": "2024-08-28 22:05:15.715644000"
+          },
+          "data": {
+            "request": {
+              "authentication_method": "user_session",
+              "body": "{\"mailbox_ids\":[\"493c6e21-7787-419b-bada-7c4f50cbb932\"]}",
+              "id": "73444211-31af-42d8-99b4-34a139cf7d4a",
+              "ip": "1.2.3.4",
+              "method": "POST",
+              "path": "/v1/message-sources/febb5bf4-2ead-47b1-b467-0ac729bf6871/deactivate",
+              "query": { },
+              "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36"
+              }
+            },
+            "id": "084732e5-7704-4bbe-ab5a-77f1aa65a737",
+            "type": "rule.deactivate"
+        }

rules/sublime_rules/sublime_rules_deleted_or_deactivated.py

@@ -0,0 +1,14 @@
+from panther_sublime_helpers import sublime_alert_context
+
+SUSPICIOUS_EVENTS = [
+    "rules.delete",
+    "rules.deactivate",
+]
+
+
+def rule(event):
+    return event.get("type") in SUSPICIOUS_EVENTS
+
+
+def alert_context(event):
+    return sublime_alert_context(event)