// To Adapt to your environment
let triggerThreshold = 10;
VMwareESXi
| where SyslogMessage has "sshd"
| where SyslogMessage contains "authentication failure"
| extend SrcUsername = extract(@'\[info\]\s+\[(.*?)\]', 1, SyslogMessage)
| extend DstHostname = extract(@'\[\d+\]\s+\[(.*?)\s+on', 1, SyslogMessage)
| extend SrcIpAddr = extract(@'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})', 1, SyslogMessage)
| summarize make_set(SrcUsername),count() by SrcIpAddr,DstHostname
| where count_ >= triggerThreshold
| extend HostCustomEntity = DstHostname
relevantTechniques:
- T1110
entityMappings:
- fieldMappings:
- columnName: HostCustomEntity
identifier: FullName
entityType: Host
- fieldMappings:
- columnName: SrcIpAddr
identifier: Address
entityType: IP
triggerThreshold: 0
description: |
Identifies a failed ESXi Shell login via SSH in a short TimeFrame. This could be suspicious activity especially if this alert is seen triggering many times within a short time frame which could be evidence of a brute-force attack. TriggerThreshold can be adapted.
requiredDataConnectors:
- connectorId: SyslogAma
datatypes:
- Syslog
triggerOperator: gt
version: 1.0.0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/VMWareESXi/Analytic Rules/ESXiMultipleFailedSSHLogin.yaml
id: 22d177d5-588c-4f1a-a332-2695f52079bb
queryFrequency: 10m
query: |
// To Adapt to your environment
let triggerThreshold = 10;
VMwareESXi
| where SyslogMessage has "sshd"
| where SyslogMessage contains "authentication failure"
| extend SrcUsername = extract(@'\[info\]\s+\[(.*?)\]', 1, SyslogMessage)
| extend DstHostname = extract(@'\[\d+\]\s+\[(.*?)\s+on', 1, SyslogMessage)
| extend SrcIpAddr = extract(@'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})', 1, SyslogMessage)
| summarize make_set(SrcUsername),count() by SrcIpAddr,DstHostname
| where count_ >= triggerThreshold
| extend HostCustomEntity = DstHostname
severity: Medium
status: Available
queryPeriod: 10m
name: VMware ESXi - Multiple Failed Shell Login via SSH
tactics:
- CredentialAccess
kind: Scheduled
