CVE-2001-1329 in AIX
Summary
by MITRE
Buffer overflow in rsh on AIX 4.2.0.0 may allow local users to gain root priveleges via a long command line argument.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 04/13/2019
The vulnerability described in CVE-2001-1329 represents a critical buffer overflow flaw within the remote shell utility rsh on AIX 4.2.0.0 operating systems. This issue stems from inadequate input validation mechanisms within the rsh implementation that fails to properly constrain the length of command line arguments passed to the program. The flaw exists at the system level where the rsh daemon does not perform adequate bounds checking on user-supplied input, creating an exploitable condition that can be leveraged by local attackers to execute arbitrary code with elevated privileges.
The technical nature of this vulnerability aligns with CWE-121, which classifies buffer overflow conditions where insufficient space is allocated for data, or where data is written beyond the boundaries of a fixed-length buffer. In this specific case, the buffer overflow occurs during command line argument processing, where the rsh daemon attempts to store user-provided command line parameters without proper length validation. When a local user provides an excessively long command line argument, the program overflows the allocated buffer space and potentially overwrites adjacent memory locations including return addresses or other critical control data structures. This memory corruption can be exploited to redirect program execution flow and ultimately achieve privilege escalation to root level access.
The operational impact of this vulnerability is significant as it transforms a local user account into a root-level privileged entity without requiring authentication or network access. Attackers can leverage this flaw by simply executing the rsh command with a specially crafted command line argument that exceeds the buffer capacity. This type of privilege escalation attack falls under the ATT&CK technique T1068, which describes 'Local Port Forwarding' and 'Exploitation for Privilege Escalation' where adversaries exploit weaknesses in local system components to gain elevated privileges. The vulnerability is particularly dangerous because it requires no network connectivity and can be exploited from within the local system, making it difficult to detect through traditional network monitoring approaches.
Mitigation strategies for CVE-2001-1329 should focus on both immediate remediation and long-term system hardening measures. The most effective immediate solution involves applying the vendor-provided security patches or updates for AIX 4.2.0.0 that address the buffer overflow in the rsh implementation. System administrators should also disable the rsh service entirely if it is not essential for operations, as the rsh protocol has inherent security weaknesses and has been largely superseded by more secure alternatives like SSH. Additionally, implementing proper input validation controls, enabling address space layout randomization, and conducting regular security audits of system binaries can help prevent similar vulnerabilities from being exploited. The vulnerability also highlights the importance of adhering to secure coding practices and conducting thorough code reviews to identify and address buffer overflow conditions in system utilities and daemon implementations. Organizations should consider implementing privilege separation mechanisms and limiting the execution of system utilities with elevated privileges to reduce the potential impact of such vulnerabilities.