CVE-1999-0244 in Radius
Summary
by MITRE
livingston radius code has a buffer overflow which can allow remote execution of commands as root.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 04/17/2026
The vulnerability identified as CVE-1999-0244 resides within the livingston radius code implementation, representing a critical buffer overflow flaw that fundamentally compromises system security. This issue affects the authentication and authorization services provided by the Livingston Radius server software, which was widely deployed in enterprise environments for network access control. The buffer overflow occurs when the software processes incoming network packets containing specially crafted data that exceeds the allocated memory buffer size, creating a condition where adjacent memory locations become overwritten. This vulnerability is particularly dangerous because it allows remote attackers to execute arbitrary code with the highest privilege level available on the system, which in this case corresponds to root access.
The technical exploitation of this buffer overflow leverages the fundamental weakness in input validation and memory management within the radius server implementation. When legitimate network authentication requests are processed, the software fails to properly validate the length of incoming data fields, particularly those related to user credentials and authentication parameters. Attackers can craft malicious packets that deliberately exceed buffer boundaries, causing the program to overwrite critical memory areas including return addresses and function pointers. This memory corruption enables attackers to redirect program execution flow to malicious code injected into the buffer space, effectively allowing remote code execution with root privileges. The vulnerability demonstrates poor coding practices and inadequate bounds checking mechanisms that violate secure programming principles and standards such as those outlined in CWE-121, which specifically addresses stack-based buffer overflow conditions.
The operational impact of this vulnerability extends far beyond simple unauthorized access, as it provides attackers with complete system compromise capabilities. Once exploited, the remote execution of commands as root enables attackers to establish persistent backdoors, modify system files, install malware, or exfiltrate sensitive data from the compromised network. Network administrators who rely on Livingston Radius servers for authentication face significant risks including unauthorized network access, data breaches, and potential lateral movement within their infrastructure. The vulnerability affects organizations that depend on legacy network access control systems, where the impact is amplified due to the difficulty in quickly patching or replacing such critical infrastructure components. This represents a classic attack vector that aligns with ATT&CK technique T1078 for Valid Accounts and T1059 for Command and Scripting Interpreter, as attackers can leverage the compromised system to execute commands and maintain persistent access.
Mitigation strategies for CVE-1999-0244 require immediate attention from system administrators and security teams responsible for network infrastructure. The most effective approach involves applying vendor-provided patches or upgrading to newer versions of the Livingston Radius software that address the buffer overflow conditions through proper input validation and memory management. Organizations should implement network segmentation and access controls to limit exposure of radius servers to untrusted networks, while also deploying intrusion detection systems to monitor for suspicious authentication traffic patterns. Additionally, system administrators should consider disabling unnecessary radius server features and implementing strict input validation at network boundaries. The vulnerability highlights the importance of regular security assessments and vulnerability management programs that can identify and remediate such critical flaws before they can be exploited by malicious actors, aligning with industry best practices for maintaining secure network infrastructure and protecting against persistent threats.