CVE-2022-24989 in NAS
Summary
by MITRE • 08/20/2023
TerraMaster NAS through 4.2.30 allows remote WAN attackers to execute arbitrary code as root via the raidtype and diskstring parameters for PHP Object Instantiation to the api.php?mobile/createRaid URI. (Shell metacharacters can be placed in raidtype because popen is used without any sanitization.) The credentials from CVE-2022-24990 exploitation can be used.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 09/13/2023
This vulnerability exists within TerraMaster Network Attached Storage devices running firmware versions up to 4.2.30 and represents a critical remote code execution flaw that can be exploited by attackers accessing the device over the internet. The vulnerability specifically targets the api.php?mobile/createRaid endpoint which processes raidtype and diskstring parameters through PHP object instantiation mechanisms. The flaw stems from insufficient input validation and sanitization practices, particularly when the popen function is invoked without proper parameter sanitization, creating a direct path for command injection attacks. The vulnerability is particularly dangerous because it allows remote attackers to execute arbitrary code with root privileges, effectively providing complete system compromise.
The technical implementation of this vulnerability leverages PHP's object instantiation capabilities combined with unsafe shell command execution. When the raidtype parameter is processed, the system uses the popen function to execute shell commands without proper sanitization of user-supplied input. This creates a classic command injection scenario where maliciously crafted input can be interpreted as shell commands rather than data. The diskstring parameter further compounds the vulnerability by allowing additional manipulation of the underlying system commands. According to CWE-77 and CWE-94 standards, this represents a command injection vulnerability that occurs through improper handling of externally-provided input. The attack vector requires only network access to the WAN interface, making it particularly dangerous for devices exposed to the internet.
The operational impact of this vulnerability is severe and encompasses complete system compromise, data theft, and potential lateral movement within networks. Successful exploitation allows attackers to execute arbitrary commands with root privileges, enabling them to modify system files, install backdoors, exfiltrate sensitive data, or establish persistent access. The vulnerability is particularly concerning because it can be exploited remotely without authentication, though the attack may benefit from credentials obtained through related vulnerabilities such as CVE-2022-24990. Once compromised, affected NAS devices can serve as entry points for broader network attacks, potentially providing attackers with access to connected systems and sensitive organizational data. The exposure of root-level privileges through this vulnerability aligns with ATT&CK technique T1059.001 for command and scripting interpreter and T1068 for exploit for privilege escalation.
Mitigation strategies for this vulnerability should include immediate firmware updates to versions that address the input sanitization issues in the affected API endpoint. Organizations should implement network segmentation to limit direct WAN access to NAS devices and consider deploying firewalls to restrict access to specific IP addresses or ranges. Network monitoring should be enhanced to detect unusual patterns in API endpoint access and command execution attempts. Additionally, implementing proper input validation and sanitization practices for all user-supplied parameters, particularly those passed to shell execution functions, would prevent similar vulnerabilities. Security teams should also conduct comprehensive vulnerability assessments of all network-attached storage devices and ensure proper access controls are in place. The vulnerability demonstrates the importance of following secure coding practices and input validation as outlined in OWASP Top 10 and NIST cybersecurity guidelines, particularly focusing on preventing injection attacks and privilege escalation scenarios.