Azure-Sentinel/Detections/W3CIISLog/ProxyShellPwn2Own.yaml

65 строки
2.5 KiB
YAML

id: 968358d6-6af8-49bb-aaa4-187b3067fb95
name: Exchange SSRF Autodiscover ProxyShell - Detection
description: |
'This query looks for suspicious request patterns to Exchange servers that fit patterns recently blogged about by PeterJson. This exploitation chain utilises an SSRF vulnerability in Exchange which eventually allows the attacker to execute arbitrary Powershell on the server.
In the example powershell can be used to write an email to disk with an encoded attachment containing a shell.
Reference: https://peterjson.medium.com/reproducing-the-proxyshell-pwn2own-exploit-49743a4ea9a1'
severity: High
requiredDataConnectors:
- connectorId: AzureMonitor(IIS)
dataTypes:
- W3CIISLog
queryFrequency: 12h
queryPeriod: 12h
triggerOperator: gt
triggerThreshold: 0
tactics:
- InitialAccess
relevantTechniques:
- T1190
query: |
let successCodes = dynamic([200, 302, 401]);
W3CIISLog
| where scStatus has_any (successCodes)
| where ipv4_is_private(cIP) == False
| where csUriStem hasprefix "/autodiscover/autodiscover.json"
| project TimeGenerated, cIP, sIP, sSiteName, csUriStem, csUriQuery, Computer, csUserName, _ResourceId, FileUri
| where (csUriQuery !has "Protocol" and isnotempty(csUriQuery))
or (csUriQuery has_any("/mapi/", "powershell"))
or (csUriQuery contains "@" and csUriQuery matches regex @"\.[a-zA-Z]{2,4}?(?:[a-zA-Z]{2,4}\/)")
or (csUriQuery contains ":" and csUriQuery matches regex @"\:[0-9]{2,4}\/")
| extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
| extend AccountName = tostring(split(csUserName, "@")[0]), AccountUPNSuffix = tostring(split(csUserName, "@")[1])
entityMappings:
- entityType: Account
fieldMappings:
- identifier: FullName
columnName: csUserName
- identifier: Name
columnName: AccountName
- identifier: UPNSuffix
columnName: AccountUPNSuffix
- entityType: Host
fieldMappings:
- identifier: FullName
columnName: Computer
- entityType: IP
fieldMappings:
- identifier: Address
columnName: cIP
- entityType: AzureResource
fieldMappings:
- identifier: ResourceId
columnName: _ResourceId
version: 1.0.3
kind: Scheduled
metadata:
source:
kind: Community
author:
name: Thomas McElroy
support:
tier: Community
categories:
domains: [ "Security - Others" ]