defense_evasion_suppression_rule_created.toml

[metadata]
creation_date = "2021/08/27"
integration = ["azure"]
maturity = "production"
updated_date = "2024/05/21"

[rule]
author = ["Austin Songer"]
description = """
Identifies the creation of suppression rules in Azure. Suppression rules are a mechanism used to suppress alerts
previously identified as false positives or too noisy to be in production. This mechanism can be abused or mistakenly
configured, resulting in defense evasions and loss of security visibility.
"""
false_positives = [
    """
    Suppression Rules can be created legitimately by a system administrator. Verify whether the user identity, user
    agent, and/or hostname should be making changes in your environment. Suppression Rules created by unfamiliar users
    should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
    """,
]
from = "now-25m"
index = ["filebeat-*", "logs-azure*"]
language = "kuery"
license = "Elastic License v2"
name = "Azure Alert Suppression Rule Created or Modified"
note = """## Setup

The Azure Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule."""
references = [
    "https://docs.microsoft.com/en-us/azure/role-based-access-control/resource-provider-operations",
    "https://docs.microsoft.com/en-us/rest/api/securitycenter/alerts-suppression-rules/update",
]
risk_score = 21
rule_id = "f0bc081a-2346-4744-a6a4-81514817e888"
severity = "low"
tags = ["Domain: Cloud", "Data Source: Azure", "Use Case: Configuration Audit", "Tactic: Defense Evasion"]
timestamp_override = "event.ingested"
type = "query"

query = '''
event.dataset:azure.activitylogs and azure.activitylogs.operation_name:"MICROSOFT.SECURITY/ALERTSSUPPRESSIONRULES/WRITE" and
event.outcome: "success"
'''


[[rule.threat]]
framework = "MITRE ATT&CK"
[[rule.threat.technique]]
id = "T1562"
name = "Impair Defenses"
reference = "https://attack.mitre.org/techniques/T1562/"


[rule.threat.tactic]
id = "TA0005"
name = "Defense Evasion"
reference = "https://attack.mitre.org/tactics/TA0005/"