CVE-2021-38681 in NAS
Summary
by MITRE • 11/20/2021
A reflected cross-site scripting (XSS) vulnerability has been reported to affect QNAP NAS running Ragic Cloud DB. If exploited, this vulnerability allows remote attackers to inject malicious code. QNAP have already disabled and removed Ragic Cloud DB from the QNAP App Center, pending a security patch from Ragic.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 11/25/2021
This vulnerability represents a critical reflected cross-site scripting flaw in QNAP Network Attached Storage devices running the Ragic Cloud DB application. The issue stems from inadequate input validation and output encoding mechanisms within the web interface components that process user-supplied data. Attackers can exploit this weakness by crafting malicious URLs containing crafted script payloads that get reflected back to users who click on the links. This type of vulnerability falls under CWE-79 which specifically addresses cross-site scripting conditions where untrusted data is incorporated into web pages without proper sanitization. The attack vector operates through web browsers that execute the injected malicious scripts in the context of the victim's session, potentially leading to session hijacking, credential theft, or unauthorized actions within the NAS environment.
The operational impact of this vulnerability extends beyond simple script execution as it compromises the integrity of the QNAP device's web interface and potentially the entire storage system. When attackers successfully inject malicious code, they can manipulate the user's browser session, steal authentication tokens, access sensitive data stored on the NAS, or even escalate privileges within the device's administrative interface. The vulnerability affects the Ragic Cloud DB application specifically, which provides database management capabilities through a web-based interface, making it particularly dangerous as it could allow attackers to access database contents, modify records, or potentially gain persistence within the network. The fact that QNAP has already removed the application from the App Center demonstrates the severity of the issue and aligns with ATT&CK technique T1566 which covers social engineering through malicious web content.
The remediation strategy requires immediate action from affected organizations to ensure the Ragic Cloud DB application is completely removed from all QNAP devices until a patched version is available from Ragic. System administrators should conduct comprehensive vulnerability assessments to identify any other potentially compromised devices within their network infrastructure. Network monitoring should be enhanced to detect suspicious traffic patterns that might indicate exploitation attempts, particularly focusing on unusual HTTP requests containing script payloads. The removal of the application from the App Center represents a temporary mitigation measure that aligns with defensive techniques outlined in ATT&CK framework under T1071 which addresses application layer protocol usage. Organizations should implement strict web application firewalls and input validation controls to prevent similar vulnerabilities in other applications. Additionally, security teams should establish monitoring procedures to detect any attempts to reinstall or reconfigure the vulnerable application and ensure proper patch management processes are in place for all networked devices.