Adversaries may use Valid Accounts to interact with a remote network share using Server Message Block (SMB). The adversary may then perform actions as the logged-on user.
SMB is a file, printer, and serial port sharing protocol for Windows machines on the same network or domain. Adversaries may use SMB to interact with file shares, allowing them to move laterally throughout a network. Linux and macOS implementations of SMB typically use Samba.
Windows systems have hidden network shares that are accessible only to administrators and provide the ability for remote file copy and other administrative functions. Example network shares include C$, ADMIN$, and IPC$. Adversaries may use this technique in conjunction with administrator-level Valid Accounts to remotely access a networked system over SMB,(Citation: Wikipedia Server Message Block) to interact with systems using remote procedure calls (RPCs),(Citation: TechNet RPC) transfer files, and run transferred binaries through remote Execution. Example execution techniques that rely on authenticated sessions over SMB/RPC are Scheduled Task/Job, Service Execution, and Windows Management Instrumentation. Adversaries can also use NTLM hashes to access administrator shares on systems with Pass the Hash and certain configuration and patch levels.(Citation: Microsoft Admin Shares)
| Capability ID | Capability Description | Mapping Type | ATT&CK ID | ATT&CK Name | Notes |
|---|---|---|---|---|---|
| security_command_center | Security Command Center | technique_scores | T1021.002 | SMB/Windows Admin Shares |
Comments
Chronicle is able to trigger an alert for net use commands detected for SMB/Windows admin shares (e.g., " net use.* (C|ADMIN|IPC)$").
This technique was scored as minimal based on low or uncertain detection coverage factor.
https://github.com/chronicle/detection-rules/blob/783e0e5947774785db1c55041b70176deeca6f46/soc_prime_rules/threat_hunting/windows/possible_system_network_connections_discovery__sysmon_windows_logs.yaral
References
|
| Capability ID | Capability Description | Mapping Type | ATT&CK ID | ATT&CK Name | Notes |
|---|---|---|---|---|---|
| amazon_virtual_private_cloud | Amazon Virtual Private Cloud | technique_scores | T1021.002 | SMB/Windows Admin Shares |
Comments
VPC security groups and network access control lists (NACLs) can be used to restrict direct access to remote services to trusted networks. This mitigates even an adversary with a valid account from accessing resources. This can be circumvented though if an adversary is able to compromise a trusted host and move laterally to a protected network. This results in an overall partial (coverage) score.
References
|
| aws_network_firewall | AWS Network Firewall | technique_scores | T1021.002 | SMB/Windows Admin Shares |
Comments
AWS Network Firewall has the ability to pass, drop, or alert on traffic based on the network protocol as well as perform deep packet inspection on the payload. This functionality can be used to only allow remote services from trusted hosts (i.e., only allow remote access traffic from certain hosts). This mapping is given a score of Partial because even though it can restrict remote services traffic from untrusted hosts, it cannot protect against an adversary using a trusted host that is permitted to use remote services as part of an attack.
References
|