Detection rules › Sigma
Serv-U Exploitation CVE-2021-35211 by DEV-0322
Detects patterns as noticed in exploitation of Serv-U CVE-2021-35211 vulnerability by threat group DEV-0322
Known false positives
- Unlikely
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Persistence |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 1: Process creation |
| Security-Auditing | Event ID 4688: A new process has been created. |
Rule body
title: Serv-U Exploitation CVE-2021-35211 by DEV-0322
id: 75578840-9526-4b2a-9462-af469a45e767
status: test
description: Detects patterns as noticed in exploitation of Serv-U CVE-2021-35211 vulnerability by threat group DEV-0322
references:
- https://www.microsoft.com/security/blog/2021/07/13/microsoft-discovers-threat-actor-targeting-solarwinds-serv-u-software-with-0-day-exploit/
author: Florian Roth (Nextron Systems)
date: 2021-07-14
modified: 2022-12-18
tags:
- attack.persistence
- attack.t1136.001
- cve.2021-35211
- detection.emerging-threats
# - threat_group.DEV-0322
logsource:
category: process_creation
product: windows
detection:
selection_whoami:
CommandLine|contains: 'whoami'
selection_cmd_1:
CommandLine|contains:
- './Client/Common/'
- '.\Client\Common\'
selection_cmd_2:
CommandLine|contains: 'C:\Windows\Temp\Serv-U.bat'
condition: selection_whoami and 1 of selection_cmd*
falsepositives:
- Unlikely
level: critical
Stages and Predicates
Stage 0: condition
selection_whoami and 1 of selection_cmd*Stage 1: selection_whoami
selection_whoami:
CommandLine|contains: 'whoami'
Stage 2: selection_cmd_1
selection_cmd_1:
CommandLine|contains:
- './Client/Common/'
- '.\Client\Common\'
Stage 3: selection_cmd_2
selection_cmd_2:
CommandLine|contains: 'C:\Windows\Temp\Serv-U.bat'
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
CommandLine | match |
| field:"CommandLine" kind:match |