CVE-2012-6151 in Mac OS X
Summary
by MITRE
Net-SNMP 5.7.1 and earlier, when AgentX is registering to handle a MIB and processing GETNEXT requests, allows remote attackers to cause a denial of service (crash or infinite loop, CPU consumption, and hang) by causing the AgentX subagent to timeout.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 10/07/2024
The vulnerability identified as CVE-2012-6151 affects Net-SNMP versions 5.7.1 and earlier, specifically when the AgentX protocol is utilized for MIB registration and GETNEXT request processing. This flaw represents a significant security concern within network management systems that rely on SNMP for monitoring and control operations. The vulnerability stems from improper handling of AgentX subagent timeouts during MIB registration processes, creating a condition where remote attackers can exploit the system's response to malformed or malicious requests.
The technical implementation of this vulnerability occurs within the AgentX subsystem of Net-SNMP, which facilitates communication between the SNMP agent and subagents that handle specific MIB modules. When an AgentX subagent registers to handle particular MIB objects and subsequently processes GETNEXT requests, the system fails to properly validate or handle timeout conditions that occur during these operations. This inadequate timeout management creates opportunities for attackers to craft specific SNMP requests that trigger the agent to enter infinite loops or consume excessive CPU resources, ultimately leading to system instability.
From an operational impact perspective, this vulnerability can result in complete service disruption for network management systems relying on Net-SNMP. The denial of service conditions can manifest as system crashes requiring manual restarts, infinite loops that consume 100% CPU utilization, or complete system hangs that prevent legitimate network management operations. Network administrators may experience complete loss of monitoring capabilities, potentially leading to undetected network issues or security breaches during the period when the system remains unresponsive. The vulnerability affects the availability aspect of the CIA security triad, compromising the system's ability to provide continuous service to authorized users.
The exploitability of this vulnerability is relatively straightforward for remote attackers who can send specially crafted SNMP requests to the affected system. The attack requires minimal privileges and can be executed from any network location where the SNMP service is accessible. This makes the vulnerability particularly dangerous in environments where SNMP services are exposed to untrusted networks or where proper network segmentation has not been implemented. The vulnerability aligns with CWE-400, which categorizes it as an "Uncontrolled Resource Consumption" issue, and can be mapped to ATT&CK technique T1499.004 for "Endpoint Denial of Service" within the context of network service disruption.
Organizations should immediately implement mitigations including upgrading to Net-SNMP versions 5.7.2 or later, which contain patches addressing this specific timeout handling issue. Network segmentation should be enforced to limit access to SNMP services, and access controls should be implemented to restrict SNMP communication to trusted management stations only. Additionally, monitoring systems should be configured to detect unusual CPU utilization patterns or service interruptions that may indicate exploitation attempts. Regular security assessments and vulnerability scanning should be conducted to identify systems running vulnerable versions of Net-SNMP, ensuring comprehensive protection across the entire network infrastructure.