CWE-403

What is CWE-403 (Exposure of File Descriptor to Unintended Control Sphere (File Descriptor Leak))?

A process opens files or sockets but does not close them before spawning a subprocess, allowing the child to access the parent resources.

Vulnerability Insights

Exposure of File Descriptor to Unintended Control Sphere (File Descriptor Leak) (CWE-403) represents a security risk across modern software systems. This weakness enables attackers to exploit resource management flaws, potentially leading to unauthorized access, data exfiltration, or system compromise. Organizations should implement defense-in-depth strategies combining static analysis, runtime monitoring, and binary analysis.

Impact on Systems

• Compromise of Application Integrity: Predictable execution flow is disrupted
• Potential Data Exposure: Depending on context, sensitive configurations may leak
• Availability Risks: Unexpected states leading to temporary denial of service

Real-World Attack Scenario

An attacker probes the system interfaces to identify areas where the input or state related to Exposure of File Descriptor to Unintended Control Sphere (File Descriptor Leak) is improperly handled. Once identified, they craft a payload tailored to the specific backend architecture. By exploiting the lack of robust structural validation, the attacker is able to force the application into an unintended state, bypassing standard business logic and achieving unauthorized outcomes.

Code Examples

Vulnerable Implementation

// VULNERABLE: Unvalidated input leading to Exposure of File Descriptor to Unintended Control Sphere (File Descriptor Leak)
function processInput(data) {
    // Missing strict validation or sanitization
    executeOrStoreConfig(data);
}

Secure Alternative

// SECURE: Proper validation mitigating Exposure of File Descriptor to Unintended Control Sphere (File Descriptor Leak)
function processInput(data) {
    if (!isValid(data)) throw new Error('Invalid input');
    const safeData = sanitize(data);
    executeOrStoreConfig(safeData);
}

Detection with Precogs AI

Precogs AI identifies exposure of file descriptor to unintended control sphere (file descriptor leak) patterns through automated binary and source code analysis, detecting CWE-403 weaknesses before they reach production. Our analysis engine examines compiled artifacts without requiring source code access, identifying CWE-403 patterns in vendor software, containers, firmware, and third-party libraries.

Remediation

Implement proper resource management controls following secure coding guidelines. Use automated scanning tools like Precogs AI to continuously monitor for CWE-403 vulnerabilities. Apply the principle of least privilege and validate all inputs from untrusted sources.