System Binary Proxy Execution

Adversaries may bypass process and/or signature-based defenses by proxying execution of malicious content with signed, or otherwise trusted, binaries. Binaries used in this technique are often Microsoft-signed files, indicating that they have been either downloaded from Microsoft or are already native in the operating system.[1] Binaries signed with trusted digital certificates can typically execute on Windows systems protected by digital signature validation. Several Microsoft signed binaries that are default on Windows installations can be used to proxy execution of other files or commands.

Similarly, on Linux systems adversaries may abuse trusted binaries such as split to proxy execution of malicious commands.[2][3]

ID: T1218
Tactic: Defense Evasion
Platforms: Linux, Windows, macOS
Defense Bypassed: Anti-virus, Application control, Digital Certificate Validation
Contributors: Hans Christoffer Gaardløs; Nishan Maharjan, @loki248; Praetorian; Wes Hurd
Version: 3.0
Created: 18 April 2018
Last Modified: 18 April 2022

Procedure Examples

ID Name Description
G0032 Lazarus Group

Lazarus Group lnk files used for persistence have abused the Windows Update Client (wuauclt.exe) to execute a malicious DLL.[4][5]


ID Mitigation Description
M1042 Disable or Remove Feature or Program

Many native binaries may not be necessary within a given environment.

M1038 Execution Prevention

Consider using application control to prevent execution of binaries that are susceptible to abuse and not required for a given system or network.

M1050 Exploit Protection

Microsoft's Enhanced Mitigation Experience Toolkit (EMET) Attack Surface Reduction (ASR) feature can be used to block methods of using using trusted binaries to bypass application control.

M1026 Privileged Account Management

Restrict execution of particularly vulnerable binaries to privileged accounts or groups that need to use it to lessen the opportunities for malicious usage.


ID Data Source Data Component
DS0017 Command Command Execution
DS0022 File File Creation
DS0011 Module Module Load
DS0029 Network Traffic Network Connection Creation
DS0009 Process OS API Execution
Process Creation
DS0024 Windows Registry Windows Registry Key Modification

Monitor processes and command-line parameters for signed binaries that may be used to proxy execution of malicious files. Compare recent invocations of signed binaries that may be used to proxy execution with prior history of known good arguments and loaded files to determine anomalous and potentially adversarial activity. Legitimate programs used in suspicious ways, like msiexec.exe downloading an MSI file from the Internet, may be indicative of an intrusion. Correlate activity with other suspicious behavior to reduce false positives that may be due to normal benign use by users and administrators.

Monitor for file activity (creations, downloads, modifications, etc.), especially for file types that are not typical within an environment and may be indicative of adversary activity.