CVE-2019-9066 in PHP Appointment Booking Script
Summary
by MITRE
PHP Scripts Mall PHP Appointment Booking Script 3.0.3 allows HTML injection in a user profile.
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Analysis
by VulDB Data Team • 07/19/2023
The vulnerability identified as CVE-2019-9066 affects PHP Scripts Mall PHP Appointment Booking Script version 3.0.3, presenting a significant security risk through HTML injection capabilities within user profiles. This flaw represents a critical weakness in the application's input validation and output sanitization mechanisms, allowing malicious actors to inject arbitrary HTML code into user profile fields. The vulnerability stems from insufficient filtering of user-supplied data before it is rendered back to other users or stored in the database, creating an environment where attackers can execute malicious scripts and potentially compromise user sessions.
The technical implementation of this vulnerability aligns with CWE-79, which describes Cross-Site Scripting (XSS) vulnerabilities occurring when untrusted data is improperly incorporated into web pages without adequate validation or encoding. In this specific case, the application fails to properly sanitize user profile inputs, particularly in fields where HTML content might be expected or allowed. The attack vector typically involves an attacker crafting malicious HTML content containing embedded JavaScript or other malicious code that gets executed when other users view the compromised profile. This vulnerability operates at the application layer and can be exploited through direct input manipulation or by leveraging other attack vectors that lead to profile modification.
The operational impact of this vulnerability extends beyond simple data corruption or display issues, as it creates potential pathways for more severe attacks including session hijacking, credential theft, and unauthorized access to sensitive user information. When attackers successfully inject HTML content into user profiles, they can potentially redirect users to malicious websites, steal cookies, or execute malicious scripts that persist across user sessions. The vulnerability affects the confidentiality, integrity, and availability of the application's user data, particularly when considering that profile information often contains personal details, contact information, and potentially sensitive business data. The risk is amplified when considering that appointment booking systems typically handle sensitive personal information and may be used in regulated environments where data protection is paramount.
Mitigation strategies for CVE-2019-9066 should focus on implementing robust input validation and output encoding mechanisms throughout the application's data flow. The primary defense involves implementing strict sanitization of all user inputs before they are processed or stored, utilizing libraries such as HTML Purifier or similar content sanitization tools that can effectively strip out malicious HTML tags while preserving legitimate content. Additionally, implementing proper Content Security Policy headers can provide an additional layer of protection against script execution. The application should enforce proper output encoding when displaying user-generated content, particularly using context-appropriate encoding mechanisms such as HTML entity encoding for web page contexts. Regular security audits and penetration testing should be conducted to identify similar vulnerabilities in other input fields and application components, as this type of vulnerability often indicates broader issues with input validation practices throughout the application. Organizations should also consider implementing web application firewalls and monitoring systems to detect and prevent exploitation attempts. The remediation process must include comprehensive testing to ensure that all user profile fields properly handle input validation without breaking legitimate functionality, while also implementing proper access controls to prevent unauthorized profile modifications. This vulnerability demonstrates the critical importance of following secure coding practices and adhering to industry standards such as those outlined in the OWASP Top Ten project, which specifically addresses XSS vulnerabilities as one of the most prevalent web application security risks.