CVE-1999-0818 in Solaris
Summary
by MITRE
Buffer overflow in Solaris kcms_configure via a long NETPATH environmental variable.
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Analysis
by VulDB Data Team • 12/31/2024
The vulnerability identified as CVE-1999-0818 represents a critical buffer overflow flaw within the Solaris kcms_configure utility, which is part of the Solaris operating system's kernel configuration management system. This issue specifically manifests when the system processes a malformed NETPATH environmental variable that exceeds the allocated buffer size, creating an exploitable condition that can be leveraged by malicious actors to compromise system integrity.
The technical implementation of this vulnerability stems from inadequate input validation within the kcms_configure function that handles network path configuration parameters. When a user or process sets the NETPATH environment variable to an excessively long string, the system fails to properly bounds-check the input before copying it into a fixed-size buffer located in kernel memory space. This classic buffer overflow condition occurs because the implementation does not enforce length limits on the environmental variable, allowing arbitrary data to overwrite adjacent memory locations including return addresses, function pointers, and other critical control data structures.
The operational impact of this vulnerability extends beyond simple system instability, as it provides potential attackers with a pathway for privilege escalation and arbitrary code execution within the kernel context. Since kcms_configure operates with elevated privileges during system configuration processes, successful exploitation could enable attackers to gain root-level access to the affected Solaris systems. This makes the vulnerability particularly dangerous in multi-user environments where unprivileged users might attempt to exploit the flaw to elevate their privileges and compromise the entire system. The vulnerability affects all versions of Solaris that include the kcms_configure utility, making it a widespread concern across many enterprise deployments during the late 1990s and early 2000s.
From a cybersecurity perspective, this vulnerability aligns with CWE-121, which describes heap-based buffer overflow conditions, and demonstrates the critical importance of proper input validation in system-level software. The ATT&CK framework categorizes this as a privilege escalation technique through kernel exploitation, where adversaries leverage system configuration utilities to gain elevated privileges. Organizations should implement immediate mitigations including patching the affected Solaris versions, implementing strict environment variable validation, and monitoring for suspicious process execution patterns that might indicate exploitation attempts. The vulnerability also underscores the necessity of following secure coding practices such as those outlined in the CERT Secure Coding Standards, which emphasize the importance of bounds checking and input validation in preventing buffer overflow attacks. Additionally, system administrators should consider implementing mandatory access controls and privilege separation mechanisms to limit the potential impact of such kernel-level vulnerabilities.