CVE-2018-20962 in CRUD Backpack
Summary
by MITRE
The Backpack\CRUD Backpack component before 3.4.9 for Laravel allows XSS via the select field type.
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Analysis
by VulDB Data Team • 11/21/2023
The vulnerability CVE-2018-20962 affects the Backpack\CRUD component for Laravel, specifically targeting versions prior to 3.4.9. This issue resides within the select field type implementation, which is a common component used in web application dashboards and content management systems. The Backpack\CRUD is widely utilized by developers to rapidly build administrative interfaces for Laravel applications, making this vulnerability particularly concerning given the component's prevalence in production environments. The vulnerability stems from insufficient input validation and output escaping mechanisms within the select field handling logic, creating a pathway for malicious actors to inject malicious scripts into the application's user interface.
The technical flaw manifests when user-provided data is processed through the select field type without proper sanitization or encoding. This vulnerability is classified as a cross-site scripting flaw under CWE-79, which specifically addresses improper neutralization of input during web page generation. The weakness occurs because the component fails to properly escape or validate data that flows from user input into the HTML output of the select field. When an attacker crafts malicious input containing script tags or other malicious payloads, these inputs are directly rendered into the HTML without adequate protection mechanisms. The vulnerability is particularly dangerous because it affects the administrative interface, which typically has elevated privileges and access to sensitive data, making it an attractive target for attackers seeking to escalate their privileges or gain unauthorized access to backend systems.
The operational impact of this vulnerability extends beyond simple script injection, as it can enable attackers to perform a range of malicious activities within the context of the vulnerable application. An attacker could potentially steal session cookies, redirect users to malicious sites, or execute arbitrary code in the context of the victim's browser. In the context of administrative interfaces, this vulnerability could allow unauthorized users to gain access to sensitive administrative functions, view confidential data, or manipulate the application's behavior. The ATT&CK framework categorizes this as a code injection technique under the T1059 category, where attackers leverage input validation weaknesses to execute malicious code. The vulnerability also aligns with T1546, which covers persistence mechanisms through malicious code injection, as attackers could use this vector to establish more permanent access to the system.
Mitigation strategies for this vulnerability include immediate patching to version 3.4.9 or later, which contains the necessary fixes for proper input validation and output escaping. Organizations should implement comprehensive input sanitization measures that validate all user-provided data against expected formats and reject any input containing potentially malicious content. The implementation of Content Security Policy headers can provide an additional layer of protection by restricting script execution and limiting the impact of successful XSS attacks. Security teams should also conduct regular vulnerability assessments of their administrative interfaces and ensure that all third-party components are kept up to date with the latest security patches. The principle of least privilege should be enforced within the administrative interface to limit the potential damage that can be caused by successful exploitation of such vulnerabilities. Additionally, implementing proper logging and monitoring mechanisms can help detect and respond to exploitation attempts in real-time, while regular security training for developers can prevent similar vulnerabilities from being introduced in future code implementations.