In cybersecurity, a File Inclusion vulnerability refers to a security flaw in web applications that allows attackers to include and execute arbitrary files on the application server hosting. This can occur when an application dynamically includes files based on user input without proper validation or sanitization.

There are two main types of file inclusion vulnerabilities:

1. Local File Inclusion (LFI): In an LFI attack, the attacker can include files already on the server. This could expose sensitive information like configuration files, log files, or source code. In some cases, the attacker can execute code within the included file.

2. Remote File Inclusion (RFI): RFI vulnerabilities are more severe than LFI. In this case, the attacker can include files from remote locations, usually through a URL. This allows them to execute arbitrary code on the server, potentially leading to a complete compromise of the system.

Impact of File Inclusion Vulnerabilities:

• Information Disclosure: Attackers can access sensitive files containing configuration data, user credentials, or confidential information.

• Remote Code Execution (RCE): Attackers can execute malicious code on the server, giving them complete control over the system.

• Denial of Service (DoS): By repeatedly including large files or files that cause errors, an attacker can overwhelm the server and make the application unavailable.

• Defacement: Attackers can modify the website's content or appearance by including malicious files.

Prevention of File Inclusion Vulnerabilities:

• Input Validation: Strictly validate and sanitize all user input before using it to include files.

• Safelisting: Only include files from a pre-approved list of safe locations.

• Disabling Remote File Inclusion: Removeƒ the ability to include files from remote locations unless necessary.

• Least Privilege: Ensure the web server process has the minimum necessary permissions to access files.

• Web Application Firewall (WAF): Implement a WAF to detect and block file inclusion attempts.

Organizations can protect their web applications from unauthorized access, data breaches, and system compromise by understanding and mitigating file inclusion vulnerabilities.

ThreatNG can significantly enhance an organization's ability to detect, assess, and mitigate the risk of File Inclusion (LFI/RFI) attacks across its entire external attack surface, including third-party and supply chain assets. Here's how:

ThreatNG's Role in Preventing File Inclusion:

Domain Intelligence Investigation Module:

• Application Discovery: ThreatNG identifies all web applications running on the organization's domains and subdomains, providing a comprehensive inventory of potential targets for file inclusion attacks.

• Exposed API Discovery: It uncovers exposed APIs, which can be vulnerable to file inclusion if they process user-supplied file paths or URLs without proper validation.

• Exposed Development Environment Discovery: ThreatNG identifies development environments accessible from the Internet. These environments often lack robust security measures and are prime targets for file inclusion attacks due to potential misconfigurations and test scripts.

• WAF Discovery and Identification: This process determines whether a Web Application Firewall (WAF) exists. WAFs can help mitigate file inclusion attempts by filtering malicious traffic and blocking known attack patterns.

• Known Vulnerabilities: ThreatNG scans web applications for known vulnerabilities, including file inclusion, using its extensive vulnerability database.

Digital Risk Protection (DRP):

• ThreatNG continuously monitors the internet for mentions of the organization's domains, subdomains, and IP addresses, alerting security teams to any discussions or activities that could indicate potential file inclusion attacks.

Security Ratings:

• ThreatNG gives an organization a comprehensive security rating based on various factors, including its susceptibility to file inclusion attacks. This allows organizations to prioritize remediation efforts.

Complementary Solutions and Handoff:

ThreatNG can integrate with various complementary solutions to enhance protection against file inclusion:

• Web Application Firewalls (WAFs): ThreatNG can feed vulnerability information to WAFs, enabling them to block file inclusion attempts more effectively.

• Intrusion Detection and Prevention Systems (IDPS): ThreatNG can alert IDPS to suspicious traffic patterns that could indicate file inclusion attacks.

• Static Application Security Testing (SAST) Tools: ThreatNG can complement SAST tools by providing a broader view of the attack surface and identifying vulnerabilities that might be missed by code analysis alone.

The handoff between ThreatNG and complementary solutions can occur through APIs, syslog feeds, or other integration mechanisms. For example, when ThreatNG discovers a vulnerability, it can automatically create a ticket in a ticketing system or send an alert to a SIEM system.

Detailed Workflow Example:

1. Discovery: ThreatNG continuously scans the organization's external attack surface, including third-party and supply chain assets.

2. Vulnerability Identification: ThreatNG identifies a web application with a parameter that appears vulnerable to LFI.

3. Alerting: ThreatNG sends the security team an alert detailing the vulnerability and the potential impact of a file inclusion attack.

4. Investigation: The security team investigates the alert and confirms the LFI vulnerability by attempting to include a harmless local file (e.g., /etc/passwd) through the parameter.

5. Mitigation: The security team remediates the vulnerability by implementing proper input validation and sanitization or using a WAF to block attempts to include files outside an allowed directory.

6. Verification: ThreatNG re-scans the application to verify that the vulnerability has been remediated.

By leveraging ThreatNG's comprehensive capabilities, organizations can proactively identify and address file inclusion risks across their entire external attack surface, significantly reducing the likelihood of successful attacks and protecting their sensitive data and systems.