CVE-2004-1767 in Solaris
Summary
by MITRE
The kernel in Solaris 2.6, 7, 8, and 9 allows local users to gain privileges by loading arbitrary loadable kernel modules (LKM), possibly involving the modload function.
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Analysis
by VulDB Data Team • 01/22/2025
The vulnerability described in CVE-2004-1767 represents a critical privilege escalation flaw within the Solaris kernel implementation across multiple versions including 2.6, 7, 8, and 9. This issue stems from insufficient access controls within the kernel's module loading mechanism, specifically involving the modload function that governs how loadable kernel modules can be dynamically inserted into the running kernel space. The flaw allows local attackers who already possess user-level access to potentially load malicious kernel modules that could elevate their privileges to root level, effectively bypassing the operating system's security model. This vulnerability directly impacts the kernel's integrity and the principle of least privilege that forms the foundation of operating system security. The modload function's inadequate validation of module loading requests creates an attack surface where unprivileged users can manipulate kernel behavior through carefully crafted module loading operations.
The technical implementation of this vulnerability exploits the kernel's failure to properly authenticate and authorize module loading operations. When a user attempts to load a kernel module, the system should validate that the operation originates from a trusted source and that the module being loaded is legitimate and authorized for execution within kernel space. However, in the affected Solaris versions, the modload function lacks proper access control checks that would normally prevent unauthorized module loading. This weakness allows attackers to bypass kernel security mechanisms and inject malicious code directly into the kernel address space, where it can execute with the highest possible privileges. The vulnerability operates at the kernel level and leverages the legitimate kernel module loading infrastructure to achieve its malicious purpose, making detection and prevention particularly challenging. From a cybersecurity perspective, this represents a classic case of insufficient authorization controls that violates fundamental security principles.
The operational impact of this vulnerability extends far beyond simple privilege escalation, as it fundamentally undermines the security model of the Solaris operating system. Once an attacker successfully loads a malicious kernel module, they can effectively take complete control of the system, potentially accessing all data, modifying system behavior, and establishing persistent backdoors. This vulnerability affects systems running Solaris 2.6 through 9, which were widely deployed in enterprise environments during the early 2000s, making it a significant concern for organizations that had not yet implemented proper security updates. The attack vector requires local access to the system, which means that the vulnerability could be exploited by users who have already gained initial access through other means, such as web application exploits or social engineering attacks. This makes the vulnerability particularly dangerous in environments where users may have legitimate access to systems but could be compromised or malicious. The impact is severe enough to warrant immediate attention and remediation, as it provides an automatic path to system compromise for any attacker with local user access.
Mitigation strategies for CVE-2004-1767 require immediate implementation of security patches provided by Sun Microsystems, as well as the application of system hardening measures that restrict kernel module loading capabilities. Organizations should implement the principle of least privilege by ensuring that only authorized personnel can perform kernel module operations, and should consider disabling loadable kernel modules entirely if they are not required for system operations. The vulnerability aligns with CWE-276, which describes improper privilege management, and represents a specific instance of insufficient authorization that allows unauthorized code execution in kernel space. From an attack framework perspective, this vulnerability would be categorized under the privilege escalation tactics in the MITRE ATT&CK framework, specifically targeting the kernel-level execution capabilities. System administrators should also implement monitoring and logging of kernel module loading activities to detect potential exploitation attempts. Additionally, regular security audits should verify that no unauthorized kernel modules are present on the system, and that proper access controls are in place to prevent unauthorized users from loading modules. The recommended approach combines immediate patching with operational security measures to provide comprehensive protection against this class of vulnerability.