Disable Crypto Hardware

Executive Summary

Disable Crypto Hardware (T1600.002) is a MITRE ATT&CK technique associated with Defense Impairment. 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.

Why Attackers Use It

Attackers use Disable Crypto Hardware because it provides a reliable way to advance their objective within the Defense Impairment tactic, often with a favorable balance of impact versus detectability on Network Devices environments. Defenders should assess this behavior in the context of the affected platform and adjacent activity rather than treating it as a standalone indicator.

MITRE Description

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). (Citation: Cisco Blog Legacy Device Attacks)

Attack Flow

1. Attacker gains the prerequisite access or context described below.
2. Attacker executes Disable Crypto Hardware to achieve its tactical objective (Defense Impairment).
3. Resulting access/data/effect is leveraged to advance the broader attack chain (see Related Techniques).

Prerequisites

• Platform(s): Network Devices
• ATT&CK does not define one universal permission requirement for this technique. Establish the required access from the observed implementation and affected platform.

Common Tools

• Tool attribution is implementation-specific. Use ATT&CK procedure examples and local telemetry to identify the binaries, services, scripts, accounts, or cloud resources involved.

Commands

No universal command represents Disable Crypto Hardware. Capture the exact command line, arguments, parent process, account, host, and execution time from the investigated environment; do not operationalize unverified examples.

Network Traffic

• Network observability is implementation-dependent. Review DNS, proxy, firewall, flow, authentication, and packet telemetry around the activity window, then correlate remote endpoints and protocol behavior with host evidence.

Windows Events

Sysmon Events

Detection Opportunities

No MITRE detection guidance published for this technique.

Relevant ATT&CK Data Sources: N/A

Sigma Rules

A universal Sigma rule would create unreliable results because this technique has no single guaranteed observable. Build detection logic from a documented behavior and supported data source, scope it to the affected platform, and validate it against benign administrative activity before deployment.

Splunk Queries

Start with the data sources named in the detection section. Scope searches by asset, identity, and time window; correlate the primary behavior with preceding access and subsequent actions. A portable query is intentionally not provided where the technique lacks a universal schema or observable.

Investigation Workflow

1. Confirm that the observed behavior is consistent with Disable Crypto Hardware and rule out expected administrative or application activity.
2. Establish the first-seen time, initiating identity, source system, target system, and affected resources.
3. Collect relevant host, identity, network, cloud, and application telemetry for the surrounding time window.
4. Correlate parent and child activity, remote connections, file or configuration changes, and related ATT&CK techniques.
5. Determine scope by searching for the same observable across peer assets and identities.
6. Preserve volatile evidence and record confidence, assumptions, and telemetry gaps before containment.

Containment

1. Isolate affected host(s)/account(s) identified during investigation.
2. Revoke or rotate any credentials/tokens potentially exposed.
3. Apply the mitigations listed below where not already enforced.
4. Validate no related techniques (see Related Techniques) were chained against the same asset.

Mitigation

No MITRE mitigations mapped to this technique.

Related Techniques

• T1600