CVE-2018-7736 in Z-BlogPHP
Summary
by MITRE
In Z-BlogPHP 1.5.1.1740, cmd.php has XSS via the ZC_BLOG_SUBNAME parameter or ZC_UPLOAD_FILETYPE parameter.
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Analysis
by VulDB Data Team • 08/05/2024
The vulnerability CVE-2018-7736 represents a cross-site scripting flaw discovered in Z-BlogPHP version 1.5.1.1740 within the cmd.php file. This security weakness allows attackers to inject malicious scripts into web applications through specific parameters, namely ZC_BLOG_SUBNAME and ZC_UPLOAD_FILETYPE, which are processed without adequate input validation or output sanitization. The issue stems from the application's failure to properly filter user-supplied data before incorporating it into dynamic web content, creating an avenue for malicious actors to execute arbitrary JavaScript code within the context of other users' browsers.
The technical exploitation of this vulnerability occurs when an attacker crafts malicious input containing script tags or other malicious code and submits it through either the ZC_BLOG_SUBNAME parameter or ZC_UPLOAD_FILETYPE parameter. When the web application processes these parameters in cmd.php without proper sanitization, the injected scripts become part of the generated HTML output. This allows attackers to perform various malicious activities including session hijacking, credential theft, defacement of web content, or redirection to malicious sites. The vulnerability specifically maps to CWE-79, which describes cross-site scripting flaws where insufficient validation of input data leads to the execution of untrusted code in the user's browser.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to compromise the entire web application's user base. An attacker could leverage this weakness to steal cookies containing session information, potentially gaining unauthorized access to user accounts and administrative privileges. The vulnerability affects the integrity and confidentiality of the web application, as user data could be exposed or modified without authorization. Additionally, the attack surface includes potential for privilege escalation if the application's administrative functions are accessible through the compromised session.
Mitigation strategies for CVE-2018-7736 should focus on implementing robust input validation and output encoding mechanisms throughout the application. Developers must ensure that all user-supplied parameters are properly sanitized before being processed or displayed in web pages, particularly in the cmd.php file and related components. The recommended approach includes implementing proper HTML entity encoding for all output, utilizing Content Security Policy (CSP) headers to restrict script execution, and applying input validation that rejects or removes potentially malicious characters. Organizations should also consider implementing web application firewalls to detect and block suspicious parameter values. This vulnerability aligns with ATT&CK technique T1059.007, which covers scripting through web shell commands, and emphasizes the importance of secure coding practices as outlined in OWASP Top Ten categories related to injection flaws. Regular security updates and patch management should be implemented to address similar vulnerabilities in the Z-BlogPHP framework and prevent exploitation of similar weaknesses in other components of the application.