T1601.002sub-technique of T1601 Modify System Image
Downgrade System Image
Network Devicesnothing on this site yetT1601.002 on attack.mitre.org
Adversaries may install an older version of the operating system of a network device to weaken security. Older operating system versions on network devices often have weaker encryption ciphers and, in general, fewer/less updated defensive features. On embedded devices, downgrading the version typically only requires replacing the operating system file in storage.
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 Downgrade System Image on Network Devices
- Defenders may observe adversary attempts to downgrade system images by monitoring for anomalous file transfers of OS image files (via TFTP, FTP, SCP), configuration changes pointing boot system variables to older image files, unexpected OS version strings after reboot, and checksum mismatches against approved baseline...
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.