Windows: Detect SysAid user.exe Loader Execution by Filename and SHA256 Hash

Flags execution of a specific SysAid-hosted Windows binary when the process image path and SHA256 match.

FreeReviewedSigma · High · v5
Product
windows
Category
process_creation
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-11-09
Updated
2026-07-31
title: "Windows: Detect SysAid user.exe Loader Execution by Filename and SHA256 Hash"
id: 53b084c6-1266-4116-a4cd-3e173e86dbdd
status: test
description: This rule identifies execution of a specific SysAid Server Tomcat webapp binary by matching its full filename and a known SHA256 hash. Such targeted loader execution is a key step in delivering additional malicious payloads, so reliably detecting it can expose early compromise activity. Telemetry relies on Windows process creation events that include both the executed image path and the file hash.
references:
  - https://www.sysaid.com/blog/service-desk/on-premise-software-security-vulnerability-notification
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2023/TA/Lace-Tempest/proc_creation_win_apt_lace_tempest_loader_execution.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2023-11-09
tags:
  - attack.execution
  - detection.emerging-threats
logsource:
  category: process_creation
  product: windows
detection:
  selection_img:
    Image|endswith: :\Program Files\SysAidServer\tomcat\webapps\usersfiles\user.exe
  selection_hash:
    Hashes|contains: SHA256=B5ACF14CDAC40BE590318DEE95425D0746E85B1B7B1CBD14DA66F21F2522BF4D
  condition: 1 of selection_*
falsepositives:
  - Unlikely
level: high
license: DRL-1.1
related:
  - id: 745ea50b-9673-4ba7-9426-cb45cf4a8e6d
    type: derived