Windows Image Load: Suspicious ksproxy.ax Loading Suggesting CVE-2024-35250

Flags Windows module loads of ksproxy.ax, a potential indicator of CVE-2024-35250 exploitation attempt activity.

FreeReviewedSigma · Medium · v5
Product
windows
Category
image_load
Author
@eyezuhk Isaac Fernandes (SigmaHQ), DRL 1.1
Published
2025-02-19
Updated
2026-07-31
title: "Windows Image Load: Suspicious ksproxy.ax Loading Suggesting CVE-2024-35250"
id: a31f9f95-4e00-4eb0-b233-b430619cf9ca
status: experimental
description: This rule flags Windows process image-load events where the loaded module ends with "\ksproxy.ax" outside common main-system directories and excluding several known user application binaries. Attackers may use such module loading behavior as part of exploitation or privilege-escalation attempts, so alerting on unexpected module paths helps surface suspicious activity. The detection relies on telemetry that records the ImageLoaded module name and the fully qualified Image path for the loading process.
references:
  - https://thehackernews.com/2024/12/cisa-and-fbi-raise-alerts-on-exploited.html
  - https://github.com/varwara/CVE-2024-35250
  - https://devco.re/blog/2024/08/23/streaming-vulnerabilities-from-windows-kernel-proxying-to-kernel-part1-en/
  - https://www.cisa.gov/known-exploited-vulnerabilities-catalog
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2024/Exploits/CVE-2024-35250/image_load_exploit_cve_2024_35250_privilege_escalation.yml
author: "@eyezuhk Isaac Fernandes, Huntrule Team"
date: 2025-02-19
tags:
  - attack.privilege-escalation
  - attack.t1068
  - cve.2024-35250
  - detection.emerging-threats
logsource:
  category: image_load
  product: windows
detection:
  selection:
    ImageLoaded|endswith: \ksproxy.ax
  filter_main_system_paths:
    Image|startswith:
      - C:\Program Files\
      - C:\Program Files (x86)\
      - C:\Windows\System32\
      - C:\Windows\SysWOW64\
  filter_optional_teams:
    Image|endswith: \AppData\Local\Microsoft\Teams\current\Teams.exe
  filter_optional_zoom:
    Image|endswith: \AppData\Roaming\Zoom\bin\Zoom.exe
  filter_optional_firefox:
    Image|endswith: \AppData\Local\Mozilla Firefox\firefox.exe
  filter_optional_chrome:
    Image|endswith: \AppData\Local\Google\Chrome\Application\chrome.exe
  filter_optional_opera:
    Image|endswith: \AppData\Local\Programs\Opera\opera.exe
  filter_optional_discord:
    Image|endswith: \AppData\Local\Discord\app-*\Discord.exe
  condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
  - Legitimate applications that use Windows Stream Interface APIs.
  - Media applications that use DirectShow filters.
level: medium
license: DRL-1.1
related:
  - id: 17ce9373-2163-4a2c-90ba-f91e9ef7a8c1
    type: derived