T1601.001sub-technique of T1601 Modify System Image
Patch System Image
Network Devicesnothing on this site yetT1601.001 on attack.mitre.org
Adversaries may modify the operating system of a network device to introduce new capabilities or weaken existing defenses. Some network devices are built with a monolithic architecture, where the entire operating system and most of the functionality of the device is contained within a single file. Adversaries may change this file in storage, to be loaded in a future boot, or in memory during runtime.
If this is happening now
Checklists and playbooks to open while the alert is still live.
Playbook for this stage
Ransomware, suspected or confirmed
Files renamed or unreadable, a ransom note, or backup deletion commands seen.
how MITRE says to see it
Detection Strategy for Patch System Image on Network Devices
- Defenders may observe adversary attempts to patch system images by monitoring for anomalous file transfers (TFTP, SCP, FTP) of image files, unauthorized CLI commands altering boot system variables, integrity check mismatches between running and baseline OS images, and runtime memory manipulation attempts.
what reduces it
- M1043 Credential Access Protection. Some embedded network devices are capable of storing passwords for local accounts in either plain-text or encrypted formats. Ensure that, where available, local passwords are always encrypted, per vendor recommendations.
- M1045 Code Signing. Many vendors provide digitally signed operating system images to validate the integrity of the software used on their platform. Make use of this feature where possible in order to prevent and/or detect attempts by adversaries to compromise the system image.
- M1046 Boot Integrity. Some vendors of embedded network devices provide cryptographic signing to ensure the integrity of operating system images at boot time. Implement where available, following vendor guidelines.
- M1027 Password Policies. Refer to NIST guidelines when creating password policies.
- M1026 Privileged Account Management. Restrict administrator accounts to as few individuals as possible, following least privilege principles. Prevent credential overlap across systems of administrator and privileged accounts, particularly between network and non-network platforms, such as servers or endpoints.
- M1032 Multi-factor Authentication. Use multi-factor authentication for user and privileged accounts. Most embedded network devices support TACACS+ and/or RADIUS. Follow vendor prescribed best practices for hardening access control.