MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Initial Access |
Rule body
id: dcb797cd-a4cd-4306-897b-7991f71d7e27
name: Cloudflare - Unexpected URI
description: |
'Detects client requests to unusual URI.'
severity: Medium
status: Available
requiredDataConnectors:
- connectorId: CloudflareDataConnector
dataTypes:
- Cloudflare
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
- InitialAccess
relevantTechniques:
- T1190
- T1133
query: |
Cloudflare
| where HttpRequestMethod =~ 'GET'
| where DstBytes != 0 or SrcBytes != 0
| where ClientRequestURI matches regex @'(127\.\d{1,3}\.\d{1,3}\.\d{1,3})|(10\.\d{1,3}\.\d{1,3}\.\d{1,3})|(172\.1[6-9]\.\d{1,3}\.\d{1,3})|(172\.2[0-9]\.\d{1,3}\.\d{1,3})|(172\.3[0-1]\.\d{1,3}\.\d{1,3})|(192\.168\.\d{1,3}\.\d{1,3})'
entityMappings:
- entityType: IP
fieldMappings:
- identifier: Address
columnName: SrcIpAddr
version: 1.0.1
kind: Scheduled
Stages and Predicates
Stage 1: source
Cloudflare
Stage 2: where
| where HttpRequestMethod =~ 'GET'
Stage 3: where
| where DstBytes != 0 or SrcBytes != 0
Stage 4: where
| where ClientRequestURI matches regex @'(127\.\d{1,3}\.\d{1,3}\.\d{1,3})|(10\.\d{1,3}\.\d{1,3}\.\d{1,3})|(172\.1[6-9]\.\d{1,3}\.\d{1,3})|(172\.2[0-9]\.\d{1,3}\.\d{1,3})|(172\.3[0-1]\.\d{1,3}\.\d{1,3})|(192\.168\.\d{1,3}\.\d{1,3})'
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
ClientRequestURI | regex_match |
| field:"ClientRequestURI" kind:regex_match |
DstBytes | ne |
| field:"DstBytes" kind:ne value:"0" |
HttpRequestMethod | eq |
| field:"HttpRequestMethod" kind:eq value:"GET" |
SrcBytes | ne |
| field:"SrcBytes" kind:ne value:"0" |