Develop Capabilities: Code Signing Certificates

Adversaries may create self-signed code signing certificates that can be used during targeting. Code signing is the process of digitally signing executables and scripts to confirm the software author and guarantee that the code has not been altered or corrupted. Code signing provides a level of authenticity for a program from the developer and a guarantee that the program has not been tampered with.[1] Users and/or security tools may trust a signed piece of code more than an unsigned piece of code even if they don't know who issued the certificate or who the author is.

Prior to Code Signing, adversaries may develop self-signed code signing certificates for use in operations.

ID: T1587.002
Sub-technique of:  T1587
Platforms: PRE
Version: 1.0
Created: 01 October 2020
Last Modified: 15 April 2021

Procedure Examples

ID Name Description
G0040 Patchwork

Patchwork has created self-signed certificates from fictitious and spoofed legitimate software companies that were later used to sign malware.[2]

G0056 PROMETHIUM

PROMETHIUM has created self-signed certificates to sign malicious installers.[3]

Mitigations

ID Mitigation Description
M1056 Pre-compromise

This technique cannot be easily mitigated with preventive controls since it is based on behaviors performed outside of the scope of enterprise defenses and controls.

Detection

Much of this activity will take place outside the visibility of the target organization, making detection of this behavior difficult. Detection efforts may be focused on related follow-on behavior, such as Code Signing or Install Root Certificate.

References