CVE-2009-3629 in TYPO3
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in the Backend subcomponent in TYPO3 4.0.13 and earlier, 4.1.x before 4.1.13, 4.2.x before 4.2.10, and 4.3.x before 4.3beta2 allow remote authenticated users to inject arbitrary web script or HTML via unspecified vectors.
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Analysis
by VulDB Data Team • 02/16/2025
The vulnerability described in CVE-2009-3629 represents a critical cross-site scripting flaw within the TYPO3 content management system's backend subcomponent. This security weakness affects multiple version ranges including TYPO3 4.0.13 and earlier, 4.1.x versions before 4.1.13, 4.2.x versions before 4.2.10, and 4.3.x versions before 4.3beta2. The vulnerability specifically targets the backend administration interface, making it particularly dangerous as it allows authenticated attackers to execute malicious scripts within the context of other users' browsers.
The technical nature of this vulnerability stems from insufficient input validation and output encoding mechanisms within the TYPO3 backend components. Attackers with valid authentication credentials can exploit unspecified vectors to inject arbitrary web scripts or HTML code into the system. This occurs when user-supplied data is not properly sanitized before being rendered in the backend interface, creating an environment where malicious payloads can be executed in the context of other authenticated users. The vulnerability classification aligns with CWE-79, which specifically addresses Cross-Site Scripting flaws in web applications.
The operational impact of this vulnerability extends beyond simple data theft or defacement. Since the backend is accessible to authenticated users, attackers can leverage this weakness to escalate privileges, manipulate administrative functions, or gain persistent access to the CMS. The authenticated nature of the attack means that an attacker would need valid credentials to exploit the vulnerability, but once compromised, the attacker could potentially perform administrative actions that are normally restricted to authorized personnel. This creates a significant risk for organizations where backend access is granted to multiple users, as a single compromised account could lead to broader system compromise.
Security practitioners should implement multiple layers of defense to mitigate this vulnerability. The primary mitigation involves upgrading to patched versions of TYPO3 where the backend XSS vulnerabilities have been addressed. Organizations should also consider implementing strict input validation policies and output encoding mechanisms within their web applications. Additionally, monitoring for suspicious activities in backend access logs can help detect potential exploitation attempts. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and persistence through web application exploitation, with the backend access providing attackers with elevated privileges within the CMS environment. The vulnerability demonstrates the importance of maintaining up-to-date security patches and implementing proper access controls in web application environments.