CVE-2022-43380 in AIX
Summary
by MITRE • 12/23/2022
IBM AIX 7.1, 7.2, 7.3, and VIOS 3.1 could allow a non-privileged local user to exploit a vulnerability in the AIX NFS kernel extension to cause a denial of service. IBM X-Force ID: 238640.
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Analysis
by VulDB Data Team • 12/24/2022
The vulnerability identified as CVE-2022-43380 affects IBM AIX operating systems version 7.1, 7.2, 7.3, and VIOS 3.1, representing a significant security concern for enterprise environments relying on these systems. This flaw exists within the AIX NFS kernel extension, which is critical for network file sharing operations in Unix-based environments. The vulnerability specifically targets the kernel-level implementation of Network File System protocols, creating a potential pathway for denial of service attacks that could severely impact system availability and business operations.
The technical flaw manifests as a vulnerability within the NFS kernel extension that allows a local, non-privileged user to exploit a condition that results in system instability. This type of vulnerability typically stems from improper handling of network file system requests or insufficient validation of input parameters within the kernel space. The vulnerability classification aligns with CWE-119, which describes weaknesses in memory management, particularly issues related to insufficient protection of memory buffers and improper handling of kernel data structures. The exploitation mechanism likely involves crafting specific NFS requests or manipulating kernel data structures in a way that triggers an unexpected system state leading to denial of service conditions.
From an operational perspective, this vulnerability presents a substantial risk to enterprise environments where AIX systems serve as critical infrastructure components. The local nature of the exploit means that attackers need only local access to a system to potentially cause denial of service, making it particularly dangerous in environments where local user access is not strictly controlled. The impact extends beyond simple service interruption as the vulnerability could be leveraged to disrupt critical business operations, especially in scenarios where AIX systems host shared storage or are part of larger distributed computing environments. Organizations utilizing IBM AIX for enterprise storage solutions or virtualization platforms would face significant operational disruption if this vulnerability were exploited.
The threat landscape for this vulnerability aligns with ATT&CK technique T1499, which covers network denial of service attacks, and more specifically T1070.004, which involves the use of system binaries to execute malicious code or cause system instability. Security teams should consider this vulnerability as part of their broader threat modeling efforts, particularly in environments where local access controls are insufficient or where the systems are not properly maintained with security patches. The vulnerability's presence in multiple AIX versions indicates a systemic issue within the NFS implementation that requires comprehensive assessment of all affected systems.
Mitigation strategies should focus on immediate patch deployment from IBM, which would address the underlying kernel extension vulnerability. Organizations should also implement additional controls such as restricting local user access to systems where NFS services are active, monitoring for unusual NFS activity patterns, and implementing proper access controls for local accounts. Network segmentation and privilege separation can help reduce the attack surface, while regular security assessments should be conducted to identify potential exploitation vectors. The vulnerability highlights the importance of maintaining current security patches and proper system hardening practices, particularly in enterprise environments where multiple system components interact through network services like NFS. Organizations should also consider implementing intrusion detection systems that can monitor for abnormal NFS behavior patterns that might indicate exploitation attempts.