Weaken Encryption: Disable Crypto Hardware

ID Name
T1600.001 Reduce Key Space
T1600.002 Disable Crypto Hardware

Adversaries disable a network device’s dedicated hardware encryption, which may enable them to leverage weaknesses in software encryption in order to reduce the effort involved in collecting, manipulating, and exfiltrating transmitted data.

Many network devices such as routers, switches, and firewalls, perform encryption on network traffic to secure transmission across networks. Often, these devices are equipped with special, dedicated encryption hardware to greatly increase the speed of the encryption process as well as to prevent malicious tampering. When an adversary takes control of such a device, they may disable the dedicated hardware, for example, through use of Modify System Image, forcing the use of software to perform encryption on general processors. This is typically used in conjunction with attacks to weaken the strength of the cipher in software (e.g., Reduce Key Space). [1]

ID: T1600.002
Sub-technique of:  T1600
Tactic: Defense Evasion
Platforms: Network
Permissions Required: Administrator
Data Sources: File monitoring
Version: 1.0
Created: 19 October 2020
Last Modified: 21 October 2020

Mitigations

This type of attack technique cannot be easily mitigated with preventive controls since it is based on the abuse of system features.

Detection

There is no documented method for defenders to directly identify behaviors that disable cryptographic hardware. Detection efforts may be focused on closely related adversary behaviors, such as Modify System Image and Network Device CLI. Some detection methods require vendor support to aid in investigation.

References