Detection rules › Sigma
OMIGOD SCX RunAsProvider ExecuteScript
Rule to detect the use of the SCX RunAsProvider ExecuteScript to execute any UNIX/Linux script using the /bin/sh shell. Script being executed gets created as a temp file in /tmp folder with a scx* prefix. Then it is invoked from the following directory /etc/opt/microsoft/scx/conf/tmpdir/. The file in that directory has the same prefix scx*. SCXcore, started as the Microsoft Operations Manager UNIX/Linux Agent, is now used in a host of products including Microsoft Operations Manager, Microsoft Azure, and Microsoft Operations Management Suite.
Known false positives
- Legitimate use of SCX RunAsProvider ExecuteScript.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Initial Access | |
| Execution | |
| Privilege Escalation |
Telemetry coverage
| Platform | Record / event type |
|---|---|
| Linux | Event ID 1: Process Create |
Rule body
title: OMIGOD SCX RunAsProvider ExecuteScript
id: 6eea1bf6-f8d2-488a-a742-e6ef6c1b67db
status: test
description: |
Rule to detect the use of the SCX RunAsProvider ExecuteScript to execute any UNIX/Linux script using the /bin/sh shell.
Script being executed gets created as a temp file in /tmp folder with a scx* prefix.
Then it is invoked from the following directory /etc/opt/microsoft/scx/conf/tmpdir/.
The file in that directory has the same prefix scx*. SCXcore, started as the Microsoft Operations Manager UNIX/Linux Agent, is now used in a host of products including
Microsoft Operations Manager, Microsoft Azure, and Microsoft Operations Management Suite.
references:
- https://www.wiz.io/blog/omigod-critical-vulnerabilities-in-omi-azure
- https://github.com/Azure/Azure-Sentinel/pull/3059
author: Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research), MSTIC
date: 2021-10-15
modified: 2022-10-05
tags:
- attack.privilege-escalation
- attack.initial-access
- attack.execution
- attack.t1068
- attack.t1190
- attack.t1203
logsource:
product: linux
category: process_creation
detection:
selection:
User: root
LogonId: 0
CurrentDirectory: '/var/opt/microsoft/scx/tmp'
CommandLine|contains: '/etc/opt/microsoft/scx/conf/tmpdir/scx'
condition: selection
falsepositives:
- Legitimate use of SCX RunAsProvider ExecuteScript.
level: high
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
User: root
LogonId: 0
CurrentDirectory: '/var/opt/microsoft/scx/tmp'
CommandLine|contains: '/etc/opt/microsoft/scx/conf/tmpdir/scx'
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
CommandLine | match |
| field:"CommandLine" kind:match value:"/etc/opt/microsoft/scx/conf/tmpdir/scx" |
CurrentDirectory | eq |
| field:"CurrentDirectory" kind:eq value:"/var/opt/microsoft/scx/tmp" |
LogonId | eq |
| field:"LogonId" kind:eq value:"0" |
User | eq |
| field:"user" kind:eq value:"root" |