https://feed.craftedsignal.io/vendors/zoho/Trending threats, MITRE ATT&CK coverage, and detection metadata — refreshed continuously.Hugoenhello@craftedsignal.iohello@craftedsignal.ioWed, 24 Jan 2024 12:00:00 +0000https://feed.craftedsignal.io/briefs/2024-01-first-time-seen-rmm/Wed, 24 Jan 2024 12:00:00 +0000hello@craftedsignal.iohttps://feed.craftedsignal.io/briefs/2024-01-first-time-seen-rmm/Detects the execution of previously unseen remote monitoring and management (RMM) tools or remote access software on compromised Windows endpoints, often leveraged for command-and-control, persistence, and execution of malicious commands.Attackers commonly abuse legitimate remote monitoring and management (RMM) tools and remote access software for command and control (C2), persistence, and execution of native commands on compromised endpoints. These tools provide attackers with the ability to maintain access, execute commands, and move laterally within a network. This detection identifies when a process associated with commonly abused RMM/remote access tools is observed for the first time on a host. The rule is designed to trigger when a new process name or code signature associated with RMM software, or a child process of such software, is seen within a configured history window. This helps defenders quickly identify potentially malicious use of legitimate tools.

Attack Chain

1. Initial Access: The attacker gains initial access to a target system through various methods, such as exploiting vulnerabilities or using compromised credentials.
2. Tool Deployment: The attacker deploys a remote monitoring and management (RMM) tool or remote access software on the compromised endpoint. This may involve downloading and installing the tool, or exploiting existing installations.
3. Persistence: The RMM tool is configured to run persistently on the system, ensuring that the attacker maintains access even after a reboot or other disruption. This may involve creating a service or adding a registry key to ensure the tool starts automatically.
4. Command and Control: The attacker uses the RMM tool to establish a command and control (C2) channel with the compromised system. This allows them to remotely execute commands, transfer files, and monitor activity on the system.
5. Lateral Movement: Using the RMM tool, the attacker moves laterally within the network, compromising additional systems and escalating their access. This may involve using the tool to access shared resources or execute commands on other systems.
6. Data Exfiltration or Ransomware Deployment: The attacker uses their access to exfiltrate sensitive data from the compromised network or deploy ransomware to encrypt files and demand a ransom payment.
7. Cleanup: The attacker may attempt to remove traces of their activity, such as logs or files associated with the RMM tool, to avoid detection.

Impact

Compromise via RMM tools can lead to significant data breaches, financial losses, and reputational damage. The use of legitimate tools makes detection more difficult. Successful attacks can result in ransomware deployment, data theft, and prolonged unauthorized access to sensitive systems. Organizations in all sectors are potentially at risk.

Recommendation

• Deploy the process creation rule to detect the execution of RMM tools on endpoints based on process.name and process.code_signature.subject_name criteria in the query.
• Enable Sysmon process creation logging (Event ID 1) to ensure the collection of necessary event data for the detection rule.
• Investigate any alerts generated by the detection rule to determine whether the execution of the RMM tool is authorized and legitimate. Refer to the references for a list of commonly abused RMM tools and associated indicators.

]]>mediumadvisoryremote-accessrmmcommand-and-controlpersistencehttps://feed.craftedsignal.io/briefs/2024-01-rmm-dns-non-browser/Wed, 03 Jan 2024 12:00:00 +0000hello@craftedsignal.iohttps://feed.craftedsignal.io/briefs/2024-01-rmm-dns-non-browser/Detection of DNS queries to remote monitoring and management (RMM) domains from non-browser processes indicating potential misuse of legitimate remote access tools for command and control.This detection identifies DNS queries to commonly abused remote monitoring and management (RMM) or remote access software domains originating from processes that are not web browsers. This activity can indicate the use of legitimate RMM tools for malicious purposes, such as command and control, persistence, or lateral movement within a network. The detection aims to surface RMM clients, scripts, or other non-browser activities contacting these services without legitimate user interaction. Defenders should investigate processes making these queries to confirm expected behavior and validate the security posture of their managed assets. The rule is based on a list of known RMM domains and excludes common browser processes to reduce false positives.

Attack Chain

1. An attacker gains initial access to a Windows host through unspecified means.
2. The attacker deploys or leverages an existing RMM tool on the compromised host.
3. The RMM tool, running as a non-browser process, initiates a DNS query to resolve a command and control server associated with the RMM service (e.g., teamviewer.com).
4. The DNS query is made by a process other than a known web browser (chrome.exe, firefox.exe, etc.).
5. The compromised host establishes a connection to the resolved IP address associated with the RMM domain.
6. The attacker uses the RMM tool to execute commands, transfer files, or perform other malicious activities on the compromised host.
7. The attacker may use the RMM tool for lateral movement, pivoting to other systems within the network.
8. The attacker achieves their objective, which could include data exfiltration, ransomware deployment, or maintaining persistent access.

Impact

Compromise via abused RMM software can lead to full system compromise, data theft, or deployment of ransomware. While the number of affected victims is unknown, the sectors most likely to be impacted include any organization that relies on RMM tools for IT management. Successful exploitation allows attackers to bypass traditional security controls by using legitimate software, making detection more challenging.

Recommendation

• Deploy the Sigma rule “DNS Queries to Known RMM Domains from Non-Browser Processes” to your SIEM and tune the RMM domain list for your environment.
• Investigate any alerts generated by the Sigma rule, focusing on identifying the process responsible for the DNS query and its parent process.
• Implement application control policies to restrict the execution of unauthorized RMM tools.
• Enable Sysmon DNS event logging to ensure the necessary data is available for the detection rule.
• Correlate with other alerts to identify potential compromises.
• Review process.code_signature for trusted RMM publishers and investigate any unsigned or unexpected signers.

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