Cross-site scripting (XSS) vulnerability in the Wir ber uns (fsmi_people) extension 0.0.24 and earlier for TYPO3 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.
Cross-Site Scripting (XSS) vulnerabilities in the Wir ber uns (fsmi_people) extension for TYPO3 allow attackers to inject malicious scripts into web pages, potentially leading to account compromise, data theft, or website defacement. This vulnerability affects versions 0.0.24 and earlier, and successful exploitation requires user interaction, making it a medium-severity risk.
Step 1: Payload Delivery: The attacker crafts a malicious payload containing HTML or JavaScript code. This payload is designed to be injected into a specific part of the web page controlled by the vulnerable extension.
Step 2: User Interaction: The attacker lures a victim into visiting a crafted URL or interacting with a specific element on the website. This interaction triggers the vulnerable code within the fsmi_people extension.
Step 3: Payload Injection: The malicious payload is processed by the extension and, due to the lack of proper sanitization, is included in the HTML output sent to the victim's browser.
Step 4: Script Execution: The victim's browser renders the HTML, including the attacker's injected JavaScript. The JavaScript code then executes within the context of the victim's browser, allowing the attacker to perform actions such as stealing cookies, redirecting the user, or defacing the website.
The vulnerability stems from a failure to properly sanitize user-supplied input before displaying it on a web page. Specifically, the fsmi_people extension likely processes user-provided data (e.g., in a form or through URL parameters) without encoding or filtering potentially malicious HTML or JavaScript code. This allows an attacker to craft a malicious payload containing HTML tags or JavaScript code, which, when rendered by a victim's browser, executes the attacker's script. The root cause is a lack of input validation and output encoding (specifically, HTML entity encoding) within the extension's code. This allows for the injection of arbitrary HTML and JavaScript.