CVE-2012-2321 in ConnMan
Summary
by MITRE
The loopback plug-in in ConnMan before 0.85 allows remote attackers to execute arbitrary commands via shell metacharacters in the (1) host name or (2) domain name in a DHCP reply.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 12/02/2021
The vulnerability identified as CVE-2012-2321 affects the ConnMan network management daemon version 0.85 and earlier, specifically targeting the loopback plug-in component. This critical security flaw resides within the network configuration handling mechanism of ConnMan, which is designed to manage network connections on Linux systems. The vulnerability stems from insufficient input validation and sanitization of network parameters received through DHCP replies, creating a pathway for remote command execution attacks. The loopback plug-in, responsible for handling local network interface configurations, processes host name and domain name parameters from DHCP servers without proper shell escaping or command injection prevention measures. This design flaw enables attackers to inject malicious shell metacharacters that get interpreted and executed by the underlying system shell when the network configuration is processed.
The technical exploitation of this vulnerability occurs through carefully crafted DHCP replies that contain malicious shell metacharacters within either the host name or domain name fields. When ConnMan processes these malformed DHCP responses through its loopback plug-in, the unescaped characters are passed directly to shell execution contexts where they are interpreted as commands rather than simple string data. This represents a classic command injection vulnerability that falls under CWE-77, which specifically addresses command injection flaws in software systems. The vulnerability is particularly dangerous because it operates at the network configuration level, meaning that attackers can exploit it without requiring direct system access or authentication. The attack vector is remote and can be initiated from any location where an attacker controls a DHCP server or can manipulate DHCP responses through network interception techniques.
The operational impact of CVE-2012-2321 extends beyond simple privilege escalation to encompass complete system compromise and potential lateral movement within network environments. An attacker who successfully exploits this vulnerability gains arbitrary command execution capabilities on the target system with the privileges of the ConnMan daemon process, typically running with elevated permissions to manage network interfaces. This allows for full system control including data exfiltration, persistence establishment, and further network reconnaissance. The vulnerability affects systems that rely on ConnMan for network management, particularly embedded devices, IoT appliances, and Linux-based systems where automatic network configuration is enabled. The attack can be particularly devastating in environments where automatic network configuration is enabled and no network segmentation is in place, as it can lead to widespread compromise of networked systems. According to ATT&CK framework, this vulnerability maps to T1059.007 for command and scripting interpreter and T1068 for exploit for privilege escalation, representing the exploitation of system services for unauthorized access.
Mitigation strategies for CVE-2012-2321 should focus on immediate patching of affected ConnMan installations to version 0.85 or later, which includes proper input sanitization and shell escaping mechanisms. Organizations should implement network segmentation and DHCP server authentication to prevent unauthorized DHCP responses from reaching target systems. Additional protective measures include disabling automatic network configuration where possible, implementing network access controls, and monitoring for unusual DHCP activity patterns. The vulnerability highlights the importance of input validation in network protocol handling components and the need for robust sanitization of all user-provided data within system services. Security teams should also consider implementing intrusion detection systems that can identify and alert on suspicious DHCP traffic patterns that may indicate exploitation attempts. Regular security assessments of network management services and proper configuration management practices are essential to prevent similar vulnerabilities from emerging in other network components.