title: Serv-U Exploitation CVE-2021-35211 by DEV-0322
id: 75578840-9526-4b2a-9462-af469a45e767
status: experimental
description: Detects patterns as noticed in exploitation of Serv-U CVE-2021-35211 vulnerability by threat group DEV-0322 
author: Florian Roth
date: 2021/07/14
references:
    - https://www.microsoft.com/security/blog/2021/07/13/microsoft-discovers-threat-actor-targeting-solarwinds-serv-u-software-with-0-day-exploit/
    - https://nvd.nist.gov/vuln/detail/cve-2021-35211
logsource:
    category: process_creation
    product: windows
tags:
    - attack.persistence
    - attack.t1136.001
    # - threat_group.DEV-0322
detection:
    selection1:
        CommandLine|contains: 'whoami'
    selection2:
        CommandLine|contains:
            - './Client/Common/'
            - '.\Client\Common\'
    selection3:
        CommandLine|contains: 'C:\Windows\Temp\Serv-U.bat'
    condition: selection1 and selection2 or selection3
falsepositives:
    - Unlikely
level: critical
