CVE-2020-8091 in TYPO3
Summary
by MITRE
svg.swf in TYPO3 6.2.0 to 6.2.38 ELTS and 7.0.0 to 7.1.0 could allow an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack on a targeted system. This may be at a contrib/websvg/svg.swf pathname.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 03/27/2024
The vulnerability identified as CVE-2020-8091 affects TYPO3 content management systems across specific version ranges including 6.2.0 through 6.2.38 ELTS and 7.0.0 through 7.1.0. This issue manifests through the svg.swf file located at contrib/websvg/svg.swf within the TYPO3 installation directory structure. The vulnerability represents a critical cross-site scripting flaw that enables remote attackers to execute malicious scripts in the context of a victim's browser without requiring authentication credentials. This particular attack vector exploits the insecure handling of user-supplied input within the svg.swf component, which serves as a flash-based SVG rendering utility within the TYPO3 ecosystem.
The technical flaw stems from insufficient input validation and sanitization within the svg.swf file, which processes SVG content that can be manipulated by attackers. When the system processes SVG files through this component, it fails to properly escape or validate user-provided parameters, creating an opportunity for malicious actors to inject arbitrary JavaScript code. This vulnerability falls under CWE-79 which specifically addresses cross-site scripting flaws in web applications, and aligns with ATT&CK technique T1203 for Exploitation for Client Execution. The attack can be executed through various means including crafted SVG files uploaded to the system or through manipulation of SVG parameters passed to the vulnerable component, allowing attackers to execute scripts in the victim's browser context with the privileges of the targeted user.
The operational impact of CVE-2020-8091 extends beyond simple script execution, as it can enable attackers to perform a wide range of malicious activities including session hijacking, data theft, and redirection to malicious websites. An attacker could leverage this vulnerability to steal user session cookies, potentially gaining unauthorized access to administrative panels or user accounts with elevated privileges. The vulnerability affects the core functionality of TYPO3's SVG handling capabilities and could compromise the integrity of the entire web application. Given that TYPO3 installations often contain sensitive content management data, the potential for data breach and system compromise is significant. The vulnerability also impacts the trust model of the web application, as users may unknowingly execute malicious code when interacting with SVG content.
Mitigation strategies for CVE-2020-8091 require immediate action including upgrading to patched versions of TYPO3 that address this vulnerability, specifically versions beyond the affected ranges mentioned in the CVE description. Organizations should implement comprehensive input validation and sanitization measures for all SVG content processing, particularly focusing on the contrib/websvg/svg.swf component. Security measures should include disabling or removing the vulnerable svg.swf file from installations where SVG functionality is not critical, implementing strict content security policies, and conducting thorough security audits of all SVG handling components. Additionally, network-level protections such as web application firewalls should be configured to monitor and block suspicious SVG content patterns. The remediation process should also involve comprehensive user education regarding the risks of uploading untrusted SVG files and implementing proper access controls to limit the impact of potential exploitation. Organizations should also consider implementing automated patch management systems to ensure timely application of security updates and maintain detailed logging of SVG-related activities for forensic analysis purposes.