Detection rules › Kusto
App Gateway WAF - Scanner Detection
'Identifies a match for a Scanner detection user agent based attack in the App Gateway WAF logs. The threshold value in the query can be changed as per your infrastructure's requirements. References: https://owasp.org/www-community/Vulnerability_Scanning_Tools'
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Reconnaissance | |
| Initial Access | |
| Execution | |
| Privilege Escalation | |
| Discovery |
Rule body
id: 9b8dd8fd-f192-42eb-84f6-541920400a7a
name: App Gateway WAF - Scanner Detection
description: |
'Identifies a match for a Scanner detection user agent based attack in the App Gateway WAF logs. The threshold value in the query can be changed as per your infrastructure's requirements.
References: https://owasp.org/www-community/Vulnerability_Scanning_Tools'
severity: High
status: Available
requiredDataConnectors:
- connectorId: WAF
dataTypes:
- AzureDiagnostics
queryFrequency: 6h
queryPeriod: 6h
triggerOperator: gt
triggerThreshold: 0
tactics:
- DefenseEvasion
- Execution
- InitialAccess
- Reconnaissance
- Discovery
relevantTechniques:
- T1548
- T1203
- T1190
- T1595
- T1046
tags:
- Scanner Detection
query: |
let Threshold = 3;
AGWFirewallLogs
| where Action == "Matched"
| where Message contains "Found User-Agent associated with security scanner"
| project TransactionId, Hostname, RequestUri, TimeGenerated, ClientIp, Message, DetailedMessage, DetailedData
| join kind = inner(
AGWFirewallLogs
| where Action == "Blocked"
) on TransactionId
| extend Uri = strcat(Hostname,RequestUri)
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), TransactionID = make_set(TransactionId), Message = make_set(Message), Detail_Message = make_set(DetailedMessage), Detail_Data = make_set(DetailedData), Total_TransactionId = dcount(TransactionId) by ClientIp, Uri, Action
| where Total_TransactionId >= Threshold
# The Threshold value above can be changed as per your infrastructure's requirement
entityMappings:
- entityType: URL
fieldMappings:
- identifier: Url
columnName: Uri
- entityType: IP
fieldMappings:
- identifier: Address
columnName: ClientIp
version: 1.0.3
kind: Scheduled
Stages and Predicates
Parameters
let Threshold = 3;
Stage 1: source
AGWFirewallLogs
Stage 2: where
| where Action == "Matched"
Stage 3: where
| where Message contains "Found User-Agent associated with security scanner"
Stage 4: project
| project TransactionId, Hostname, RequestUri, TimeGenerated, ClientIp, Message, DetailedMessage, DetailedData
Stage 5: join
| join kind = inner(
AGWFirewallLogs
| where Action == "Blocked"
) on TransactionId
Stage 6: extend
| extend Uri = strcat(Hostname,RequestUri)
Stage 7: summarize
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), TransactionID = make_set(TransactionId), Message = make_set(Message), Detail_Message = make_set(DetailedMessage), Detail_Data = make_set(DetailedData), Total_TransactionId = dcount(TransactionId) by ClientIp, Uri, Action
Stage 8: where
| where Total_TransactionId >= Threshold
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
Action | eq |
| field:"Action" kind:eq |
Message | contains |
| field:"Message" kind:contains value:"Found User-Agent associated with security scanner" |
Total_TransactionId | ge |
| field:"Total_TransactionId" kind:ge value:"3" |
Output fields
These fields are emitted when the rule matches.
| Field | Source |
|---|---|
Action | summarize |
ClientIp | summarize |
Detail_Data | summarize |
Detail_Message | summarize |
EndTime | summarize |
Message | summarize |
StartTime | summarize |
Total_TransactionId | summarize |
TransactionID | summarize |
Uri | summarize |