CVE-2008-2236 in blosxom
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in blosxom.cgi in Blosxom before 2.1.2 allows remote attackers to inject arbitrary web script or HTML via the flav parameter (flavour variable). NOTE: some of these details are obtained from third party information.
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Analysis
by VulDB Data Team • 10/09/2018
The vulnerability identified as CVE-2008-2236 represents a classic cross-site scripting flaw in the Blosxom blogging platform, specifically affecting versions prior to 2.1.2. This issue resides in the blosxom.cgi script where the flav parameter, also known as the flavour variable, fails to properly sanitize user input before incorporating it into the web page output. The flaw enables remote attackers to execute malicious scripts in the context of other users' browsers who view the affected content, creating a significant security risk for web applications that rely on this blogging platform.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding mechanisms within the Blosxom application. When users specify a flavour parameter to customize their blog's appearance, the application processes this parameter without adequate sanitization measures. This allows malicious actors to inject HTML tags or JavaScript code directly into the parameter value, which then gets rendered in the browser alongside legitimate content. The vulnerability specifically manifests when the flav parameter contains unescaped characters that can be interpreted as executable code by web browsers, making it a prime example of improper input handling as classified under CWE-79. The flaw operates at the application layer where user-supplied data flows directly into the HTTP response without proper context-aware encoding.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform various malicious activities including session hijacking, credential theft, and data exfiltration. An attacker could craft a malicious flav parameter that, when viewed by a victim, executes scripts to steal cookies or session tokens, effectively compromising user authentication. The vulnerability affects any user who views a page containing the malicious flavour parameter, potentially impacting all visitors to a compromised blog. According to ATT&CK framework, this vulnerability maps to T1059.001 (Command and Scripting Interpreter: JavaScript) and T1531 (Account Access Removal) when considering the potential for session manipulation and credential compromise. The attack surface is particularly concerning as it requires minimal user interaction beyond viewing the compromised page, making it a persistent threat vector for social engineering campaigns.
Mitigation strategies for CVE-2008-2236 should focus on immediate patching of the Blosxom application to version 2.1.2 or later where the vulnerability has been addressed. Organizations should implement proper input validation and output encoding mechanisms for all user-supplied parameters, ensuring that any data entering the application is sanitized before being processed or displayed. The implementation of Content Security Policy headers can provide additional defense-in-depth measures by restricting the sources from which scripts can be executed. Regular security audits and input validation testing should be conducted to identify similar vulnerabilities in other application components. Security professionals should also consider implementing web application firewalls that can detect and block suspicious parameter values, particularly those containing common XSS attack patterns. The vulnerability highlights the critical importance of proper input sanitization and output encoding practices, aligning with OWASP Top Ten security principles and emphasizing the need for secure coding practices throughout the software development lifecycle.