Windows: Potential Process Injection via Msra.exe Spawning Suspicious Child Processes
Flags Msra.exe spawning suspicious tools that may indicate process injection or post-exploitation activity on Windows.
- Product
- windows
- Category
- process_creation
- Author
- Alexander McDonald (SigmaHQ), DRL 1.1
- Published
- 2022-06-24
- Updated
- 2026-07-30
ATT&CK techniques
Priv Esc → Defense EvasionRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule identifies potential process injection activity by flagging when Msra.exe spawns child processes associated with command execution, discovery, and system interrogation. Attackers may use Msra.exe to blend into legitimate remote assistance activity while running additional tooling through spawned binaries. The detection relies on process creation telemetry capturing parent process image and command line, along with the spawned child process image names.
Reporting behind it
- microsoft.comhttps://www.microsoft.com/security/blog/2021/12/09/a-closer-look-at-qakbots-latest-building-blocks-and-how-to-knock-them-down/
- fortinet.comhttps://www.fortinet.com/content/dam/fortinet/assets/analyst-reports/ar-qakbot.pdf
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_msra_process_injection.yml
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: "Windows: Potential Process Injection via Msra.exe Spawning Suspicious Child Processes"
id: a4dc5806-2807-4559-988c-ff2ac5e056da
status: test
description: This rule identifies potential process injection activity by flagging when Msra.exe spawns child processes associated with command execution, discovery, and system interrogation. Attackers may use Msra.exe to blend into legitimate remote assistance activity while running additional tooling through spawned binaries. The detection relies on process creation telemetry capturing parent process image and command line, along with the spawned child process image names.
references:
- https://www.microsoft.com/security/blog/2021/12/09/a-closer-look-at-qakbots-latest-building-blocks-and-how-to-knock-them-down/
- https://www.fortinet.com/content/dam/fortinet/assets/analyst-reports/ar-qakbot.pdf
- https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_msra_process_injection.yml
author: Alexander McDonald, Huntrule Team
date: 2022-06-24
modified: 2023-02-03
tags:
- attack.privilege-escalation
- attack.stealth
- attack.t1055
logsource:
category: process_creation
product: windows
detection:
selection:
ParentImage|endswith: \msra.exe
ParentCommandLine|endswith: msra.exe
Image|endswith:
- \arp.exe
- \cmd.exe
- \net.exe
- \netstat.exe
- \nslookup.exe
- \route.exe
- \schtasks.exe
- \whoami.exe
condition: selection
falsepositives:
- Legitimate use of Msra.exe
level: high
license: DRL-1.1
related:
- id: 744a188b-0415-4792-896f-11ddb0588dbc
type: derived