Source: vulnreport@tenable.com
All known versions of the Netgear Genie Installer for macOS contain a local privilege escalation vulnerability. The installer of the macOS version of Netgear Genie handles certain files in an insecure way. A malicious actor who has local access to the endpoint on which the software is going to be installed may overwrite certain files to obtain privilege escalation to root.
Netgear Genie Installer for macOS suffers from a critical local privilege escalation vulnerability. An attacker with local access can exploit insecure file handling during installation to gain root-level access, potentially compromising the entire system. This allows for complete system control and data exfiltration.
Step 1: Local Access: The attacker gains local access to the macOS endpoint where the Netgear Genie software is to be installed. This could be through physical access, social engineering, or a pre-existing vulnerability.
Step 2: File Overwrite Preparation: The attacker identifies a file that the Netgear Genie installer writes to during installation and that is writable by the attacker's user account or can be controlled by the attacker. This file is often located in a directory where the attacker has write access, or the installer's logic allows for path manipulation.
Step 3: Payload Creation: The attacker crafts a malicious payload, such as a shell script, a binary, or a configuration file, designed to execute commands with root privileges. This payload is prepared to be written to a location that the installer will write to.
Step 4: File Replacement: The attacker replaces the target file with their malicious payload or modifies the installer's configuration to point to their payload. This could involve overwriting the file directly or manipulating the installer's behavior.
Step 5: Installation Trigger: The attacker initiates the Netgear Genie installation process. This triggers the installer to write the attacker's payload to the specified location.
Step 6: Privilege Escalation: During or after installation, the attacker's payload is executed with root privileges, granting the attacker complete control over the system.
The vulnerability stems from insecure file handling within the Netgear Genie Installer for macOS. Specifically, the installer likely uses a privileged process to write files to the system during installation. The flaw lies in the installer's failure to properly validate or sanitize file paths or permissions before writing to them. This allows an attacker to overwrite critical system files, such as those used for launching applications or setting up system configurations. The attacker can then manipulate the installer to write a malicious payload to a location where it will be executed with elevated privileges, effectively escalating their local user privileges to root.
While no specific APTs are directly linked, this type of vulnerability is attractive to any attacker seeking to gain persistent access. It could be leveraged by various threat actors, including those focused on espionage or ransomware. Not listed on CISA KEV.
Monitor file system activity for unexpected file modifications during Netgear Genie installation, especially in system directories.
Analyze installer logs for unusual file creation or modification events.
Examine the contents of files written by the installer for malicious code.
Monitor for the execution of unexpected processes with root privileges after Netgear Genie installation.
Implement file integrity monitoring (FIM) to detect unauthorized changes to critical system files.
Uninstall Netgear Genie software if not essential. Consider alternative network management solutions.
Update to the latest version of Netgear Genie, which should include a patch for this vulnerability. Verify the patch has been applied.
Implement strict file permissions and access controls to prevent unauthorized file modifications.
Use a host-based intrusion detection system (HIDS) to monitor for suspicious activity.
Regularly audit system logs and file integrity to detect any malicious activity.
Implement a least-privilege access model for all user accounts.
Consider using a security information and event management (SIEM) system to centralize and analyze security events.