sigmahighHunting

Potential Vcruntime140 DLL Sideloading

Detects potential DLL sideloading of vcruntime140.dll, a common C++ runtime library. Threat actors have been observed using DLL sideloading techniques to load malicious payloads under the guise of legitimate applications such as SqlWriter, SqlDumper etc. Notably, APT29 has been documented leveraging WinELOADER to sideload vcruntime140.dll for executing malicious code.

MITRE ATT&CK

T1574.001

persistenceprivilege-escalationexecution

Detection Query

selection:
  ImageLoaded|endswith: \vcruntime140.dll
filter_main_legitimate_path:
  ImageLoaded|startswith:
    - C:\Windows\System32\
    - C:\Windows\SysWOW64\
    - C:\Program Files\
    - C:\Program Files (x86)\
filter_main_legitimate_signer:
  Signed: true
  SignatureStatus: Valid
  Description|endswith: C Runtime Library
filter_optional_onedrive:
  Image|startswith: C:\Users\
  Image|contains: \AppData\Local\Microsoft\OneDrive\
condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*

Author

Swachchhanda Shrawan Poudel (Nextron Systems)

Created

2026-01-12

Data Sources

windowsImage Load Events

Platforms

windows

References

Tags

attack.persistenceattack.privilege-escalationattack.executionattack.stealthattack.t1574.001

Raw Content

title: Potential Vcruntime140 DLL Sideloading
id: d7a63acb-1284-49bc-bfea-7771146c8b1c
status: experimental
description: |
    Detects potential DLL sideloading of vcruntime140.dll, a common C++ runtime library.
    Threat actors have been observed using DLL sideloading techniques to load malicious payloads under the guise of legitimate applications such as SqlWriter, SqlDumper etc.
    Notably, APT29 has been documented leveraging WinELOADER to sideload vcruntime140.dll for executing malicious code.
references:
    - https://www.mandiant.com/resources/blog/apt29-wineloader-german-political-parties
    - https://www.zscaler.com/blogs/security-research/european-diplomats-targeted-spikedwine-wineloader
    - https://www.nextron-systems.com/2023/09/15/detecting-janelarat-with-yara-and-thor/
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2026-01-12
modified: 2026-05-18
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.execution
    - attack.stealth
    - attack.t1574.001
logsource:
    category: image_load
    product: windows
detection:
    selection:
        ImageLoaded|endswith: '\vcruntime140.dll'
    filter_main_legitimate_path:
        ImageLoaded|startswith:
            - 'C:\Windows\System32\'
            - 'C:\Windows\SysWOW64\'
            - 'C:\Program Files\'
            - 'C:\Program Files (x86)\'
    filter_main_legitimate_signer:
        Signed: true
        SignatureStatus: 'Valid'
        Description|endswith: 'C Runtime Library'
    filter_optional_onedrive:
        Image|startswith: 'C:\Users\'
        Image|contains: '\AppData\Local\Microsoft\OneDrive\'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Unknown
level: high
regression_tests_path: regression_data/rules/windows/image_load/image_load_side_load_vcruntime140/info.yml