CVE-2021-21738 in ZXIPTV
Summary
by MITRE • 08/06/2021
ZTE's big video business platform has two reflective cross-site scripting (XSS) vulnerabilities. Due to insufficient input verification, the attacker could implement XSS attacks by tampering with the parameters, to affect the operations of valid users. This affects:
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Analysis
by VulDB Data Team • 08/10/2021
The vulnerability identified as CVE-2021-21738 affects ZTE's big video business platform and represents a critical security flaw in the system's input validation mechanisms. This issue manifests as two reflective cross-site scripting vulnerabilities that exploit inadequate parameter sanitization within the platform's web interface. The vulnerability stems from the platform's failure to properly validate and sanitize user input before processing, creating an attack surface where malicious actors can inject malicious scripts into web pages viewed by other users. The reflective nature of these vulnerabilities means that the malicious script is reflected off the web server back to the victim's browser, making it particularly dangerous as it can be delivered through crafted URLs or form submissions without requiring persistent storage on the server. This type of vulnerability directly maps to CWE-79 which specifically addresses cross-site scripting flaws in web applications, and aligns with ATT&CK technique T1059.003 for script injection attacks. The affected platform's architecture appears to process user-supplied parameters without adequate sanitization, allowing attackers to manipulate input fields and inject malicious JavaScript code that executes in the context of legitimate user sessions.
The operational impact of this vulnerability extends beyond simple script execution to encompass potential session hijacking, credential theft, and unauthorized access to sensitive video content managed through the platform. When valid users interact with the compromised platform, their browsers execute the injected scripts, which can perform actions such as stealing session cookies, redirecting users to malicious sites, or modifying the platform's interface to deceive users into revealing confidential information. The vulnerability affects the platform's business operations by potentially compromising user data integrity and creating opportunities for attackers to gain unauthorized access to video content and associated metadata. Given that this is a big video business platform, the implications are particularly severe as it likely handles sensitive corporate communications, personal videos, or broadcast content that could be exploited for financial gain or reputational damage. The reflected nature of the attack means that users must be tricked into clicking malicious links, but once executed, the attack can persist across multiple user sessions and potentially compromise the entire platform's user base. Attackers can leverage this vulnerability to establish persistent access to the platform and could potentially use it as a stepping stone for more sophisticated attacks within the organization's network infrastructure.
Mitigation strategies for CVE-2021-21738 should prioritize immediate implementation of robust input validation and output encoding mechanisms throughout the platform's web interface. The most effective approach involves implementing comprehensive parameter sanitization at all entry points where user input is processed, ensuring that any potentially malicious content is properly escaped or filtered before being rendered in web pages. Organizations should deploy web application firewalls to detect and block suspicious input patterns that could indicate XSS attempts, while also implementing proper content security policies to prevent execution of unauthorized scripts. The platform should enforce strict input validation using allow-list approaches rather than deny-list methods, ensuring that only expected data formats and content types are accepted. Additionally, implementing proper HTTP headers such as X-Content-Type-Options and X-Frame-Options can help reduce the attack surface by preventing MIME type sniffing and clickjacking attempts. Regular security testing including automated scanning and manual penetration testing should be conducted to identify similar vulnerabilities in the platform's codebase, while also ensuring that all input fields are properly sanitized before processing. The vulnerability's classification as a reflective XSS issue indicates that the platform's developers need to implement proper output encoding for all user-supplied data that appears in web responses, making the implementation of secure coding practices a critical requirement for preventing future occurrences of this type of vulnerability.