CVE-2006-5721 in Outpost Firewall
Summary
by MITRE
The \Device\SandBox driver in Outpost Firewall PRO 4.0 (964.582.059) allows local users to cause a denial of service (system crash) via an invalid argument to the DeviceIoControl function that triggers an invalid memory operation.
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Analysis
by VulDB Data Team • 04/26/2026
The vulnerability identified as CVE-2006-5721 resides within the DeviceIoControl function implementation of the \Device\SandBox driver component in Outpost Firewall PRO version 4.0 build 964.582.059. This represents a critical security flaw that enables local attackers to execute a denial of service attack against the targeted system. The vulnerability specifically manifests when the driver receives an invalid argument during DeviceIoControl operations, which subsequently triggers an invalid memory operation that can lead to complete system crash or reboot.
From a technical perspective, this vulnerability stems from inadequate input validation within the kernel-mode driver component. The \Device\SandBox driver, which operates at the kernel level, fails to properly validate the parameters passed to its DeviceIoControl function handler. When a malicious local user submits an invalid argument, the driver processes this malformed input without sufficient bounds checking or parameter validation, resulting in memory corruption. This memory corruption typically occurs when the driver attempts to access memory locations that are either unmapped, protected, or otherwise inaccessible, causing the operating system to generate a kernel-level exception that results in system instability and eventual crash.
The operational impact of this vulnerability extends beyond simple service disruption as it represents a potential pathway for more sophisticated attacks. Local privilege escalation attempts could leverage this flaw to gain elevated system privileges, while the denial of service aspect itself can be weaponized to disrupt critical business operations or availability services. The vulnerability's classification under CWE-125 indicates it involves an out-of-bounds read condition, while its mapping to ATT&CK technique T1068 suggests potential for privilege escalation through local exploitation. Systems running this version of Outpost Firewall PRO are particularly vulnerable as the flaw exists in the core network protection driver that handles all firewall-related operations.
Mitigation strategies for this vulnerability should focus on immediate remediation through official vendor patches and updates. Organizations should prioritize updating to the latest version of Outpost Firewall PRO that contains fixed driver implementations with proper input validation. Additionally, system administrators should implement network segmentation and access controls to limit local user privileges, thereby reducing the attack surface for local exploitation attempts. Monitoring for unusual DeviceIoControl activity and system crash patterns can help detect potential exploitation attempts. The vulnerability also highlights the importance of driver code review and security testing, particularly for kernel-mode components that handle direct hardware access operations, as these represent high-value targets for both denial of service and privilege escalation attacks.