CVE-2006-2227 in PunBB
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in misc.php in PunBB 1.2.11 allows remote attackers to inject arbitrary web script or HTML via the req_message parameter, because the value of the redirect_url parameter is not sanitized.
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Analysis
by VulDB Data Team • 07/25/2018
The CVE-2006-2227 vulnerability represents a classic cross-site scripting flaw in the PunBB 1.2.11 forum software that demonstrates the critical importance of input validation and output sanitization in web applications. This vulnerability specifically targets the misc.php script within the PunBB platform, where the req_message parameter fails to properly sanitize user input before processing. The flaw arises from the application's improper handling of the redirect_url parameter, which creates an avenue for malicious actors to inject arbitrary web scripts or HTML code into the application's response. The vulnerability's exploitation potential stems from the fact that the application does not adequately validate or escape user-supplied data before incorporating it into dynamic web content, making it susceptible to client-side code injection attacks.
The technical execution of this XSS vulnerability occurs when an attacker crafts a malicious payload containing script code and submits it through the req_message parameter. When the vulnerable application processes this input and includes the unsanitized redirect_url value in its response, the embedded malicious code gets executed within the context of the victim's browser. This creates a persistent threat vector where attackers can manipulate user sessions, steal cookies, perform unauthorized actions on behalf of users, or redirect victims to malicious websites. The vulnerability's classification as a reflected XSS issue means that the malicious script is reflected back to the user through the application's response, making it particularly dangerous for web applications that do not properly sanitize all user-controllable input parameters.
From an operational impact perspective, this vulnerability presents significant risks to PunBB 1.2.11 installations as it enables attackers to compromise user sessions and potentially gain unauthorized access to forum accounts. The attack surface is particularly concerning because forum platforms typically contain sensitive user information including personal details, private messages, and potentially confidential discussions. Security practitioners should note that this vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws in web applications. The ATT&CK framework categorizes this type of vulnerability under T1566, specifically targeting the initial access phase through malicious web content, where adversaries leverage XSS vulnerabilities to establish footholds within target environments.
The mitigation strategy for CVE-2006-2227 requires immediate implementation of proper input sanitization and output encoding mechanisms throughout the application. Organizations should ensure that all user-controllable parameters, particularly those used in redirect operations, undergo rigorous validation and sanitization before being processed or rendered in web responses. The recommended approach involves implementing strict input validation that rejects or escapes potentially malicious characters, combined with proper output encoding that converts special characters into their HTML-safe equivalents. Security teams should also consider implementing Content Security Policy (CSP) headers as an additional defense-in-depth measure to prevent execution of unauthorized scripts. Additionally, upgrading to patched versions of PunBB 1.2.11 or migrating to more secure forum platforms represents the most effective long-term solution to eliminate this vulnerability from the application environment.