CVE-2008-5656 in TYPO3
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in the frontend plugin for the felogin system extension in TYPO3 4.2.0, 4.2.1 and 4.2.2 allows remote attackers to inject arbitrary web script or HTML via unknown vectors.
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Analysis
by VulDB Data Team • 10/22/2018
The CVE-2008-5656 vulnerability represents a critical cross-site scripting flaw within the frontend plugin of TYPO3's felogin system extension across versions 4.2.0 through 4.2.2. This vulnerability resides in the authentication system component that handles user login functionality, making it particularly dangerous as it can be exploited during the most fundamental user interaction with the web application. The flaw allows remote attackers to inject malicious scripts or HTML content that executes in the context of other users' browsers, potentially compromising user sessions and accessing sensitive data. The vulnerability's impact extends beyond simple script injection as it can be leveraged to perform session hijacking, deface websites, or redirect users to malicious sites.
The technical implementation of this XSS vulnerability stems from inadequate input validation and output sanitization within the felogin plugin's frontend handling code. Attackers can exploit this by manipulating parameters or form fields that are not properly escaped before being rendered back to users. The vulnerability's classification under CWE-79 indicates a failure to properly escape output, allowing malicious code to be executed in the browser context of legitimate users. The attack vector operates through the authentication interface where user input is processed without sufficient sanitization, creating an environment where crafted payloads can persist and execute. This weakness typically manifests when user-supplied data is directly incorporated into HTML responses without proper encoding or filtering mechanisms.
The operational impact of CVE-2008-5656 extends significantly beyond simple data corruption or display issues. When exploited, this vulnerability can lead to complete session compromise, allowing attackers to impersonate legitimate users and gain unauthorized access to protected resources. The vulnerability affects not only individual user accounts but can also impact the entire website's integrity by enabling attackers to modify content or redirect traffic. In enterprise environments where TYPO3 serves as a content management platform, this vulnerability can facilitate broader attacks including privilege escalation, data exfiltration, and persistent backdoor establishment. The attack surface is particularly concerning given that the felogin plugin handles authentication, making it a prime target for initial compromise and lateral movement within networks.
Mitigation strategies for CVE-2008-5656 must address both immediate remediation and long-term security posture improvements. The most direct solution involves upgrading to TYPO3 versions that contain patches for this vulnerability, specifically versions beyond 4.2.2. Organizations should implement comprehensive input validation and output encoding mechanisms throughout their web applications, following secure coding practices that align with OWASP Top Ten recommendations. The implementation of Content Security Policy headers can provide additional defense-in-depth measures against XSS attacks by restricting script execution sources. Security teams should also conduct regular vulnerability assessments and penetration testing to identify similar weaknesses in other components of their TYPO3 installations. Network monitoring and intrusion detection systems should be configured to detect anomalous patterns that may indicate exploitation attempts, while user education programs should emphasize the importance of not clicking suspicious links or entering credentials on untrusted sites. The vulnerability underscores the importance of maintaining up-to-date software versions and implementing robust security controls as outlined in NIST cybersecurity frameworks and ISO 27001 standards.