Detection rules › Kusto
Cisco WSA - Multiple errors to URL
'Detects multiple connection errors to URL.'
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Command & Control |
Rule body
id: 1db49647-435c-41ad-bf8c-7130ba75429d
name: Cisco WSA - Multiple errors to URL
description: |
'Detects multiple connection errors to URL.'
severity: Medium
status: Available
requiredDataConnectors:
- connectorId: SyslogAma
datatypes:
- Syslog
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
- CommandAndControl
relevantTechniques:
- T1102
query: |
let threshold = 5;
CiscoWSAEvent
| where DvcAction =~ 'NONE'
| summarize count() by SrcUserName, UrlOriginal, bin(TimeGenerated, 5m)
| where count_ >= threshold
| extend URLCustomEntity = UrlOriginal, AccountCustomEntity = SrcUserName
entityMappings:
- entityType: URL
fieldMappings:
- identifier: Url
columnName: URLCustomEntity
- entityType: Account
fieldMappings:
- identifier: Name
columnName: AccountCustomEntity
version: 1.0.2
kind: Scheduled
Stages and Predicates
Parameters
let threshold = 5;
Stage 1: source
CiscoWSAEvent
Stage 2: where
| where DvcAction =~ 'NONE'
Stage 3: summarize
| summarize count() by SrcUserName, UrlOriginal, bin(TimeGenerated, 5m)
Stage 4: where
| where count_ >= threshold
Stage 5: extend
| extend URLCustomEntity = UrlOriginal, AccountCustomEntity = SrcUserName
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
DvcAction | eq |
| field:"DvcAction" kind:eq value:"NONE" |
count_ | ge |
| field:"count_" kind:ge value:"5" |
Output fields
These fields are emitted when the rule matches.
| Field | Source |
|---|---|
SrcUserName | summarize |
UrlOriginal | summarize |
AccountCustomEntity | extend |
URLCustomEntity | extend |