CVE-2026-78047 in Dimension
Summary
by MITRE • 08/28/2026
A stored cross-site scripting (XSS) vulnerability in WatchGuard Dimension's task scheduling feature allows a low-privileged authenticated administrator to inject arbitrary HTML/JavaScript into these fields, which then executes in the browser session of any other user.
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Analysis
by VulDB Data Team • 08/28/2026
The identified security flaw resides within the task scheduling module of WatchGuard Dimension, specifically affecting how input data is processed and rendered by the web interface. This vulnerability classifies as a stored cross-site scripting (XSS) issue, which represents a significant risk to application integrity because malicious payloads are persistently saved on the target server rather than being transiently passed via URL parameters or headers. The root cause lies in insufficient validation and sanitization of user-supplied input fields associated with task configuration. When an authenticated administrator submits data containing HTML tags or JavaScript code, the system fails to properly encode these characters before storing them in the backend database. Consequently, when this tainted data is subsequently retrieved and displayed within the application's web interface for any viewing user, the browser interprets the embedded scripts as executable content rather than static text.
The exploitation of this vulnerability requires a low-privileged authenticated administrator account, which lowers the barrier to entry for attackers who have already compromised or been granted such credentials through phishing, credential stuffing, or other initial access vectors. Once inside the application with these privileges, an attacker can craft malicious task definitions that include script injection payloads. These payloads are then stored permanently until manually deleted by a system administrator. The operational impact is severe because every user who accesses the affected pages to view scheduled tasks will have their browser session compromised. This allows for the execution of arbitrary JavaScript in the context of the vulnerable application, effectively bypassing same-origin policy restrictions and granting the attacker control over the victim's interaction with the site.
From a tactical perspective, this vulnerability aligns closely with CWE-79, which describes Improper Neutralization of Input During Web Page Generation commonly known as Cross-site Scripting. The specific mechanism here involves stored persistence, distinguishing it from reflected or DOM-based variants by ensuring the payload survives across multiple user sessions and page loads. In terms of MITRE ATT&CK mapping, this activity falls under T1059 Command and Control scripting, specifically JavaScript execution within a browser environment. Attackers can leverage this capability to perform session hijacking by stealing authentication cookies, performing keylogging to capture sensitive administrative credentials, or conducting drive-by downloads if the injected script facilitates navigation to malicious external domains. The ability to execute code in the context of an enterprise security management console amplifies the risk significantly, as it may lead to broader network compromise through lateral movement using stolen admin tokens.
Mitigation strategies must address both immediate remediation and long-term architectural improvements. WatchGuard has released software updates that patch this vulnerability by implementing strict input validation and output encoding mechanisms within the task scheduling feature. Administrators should immediately apply these patches to all affected instances of WatchGuard Dimension. In addition to updating, organizations should enforce principle of least privilege by ensuring that only highly trusted personnel have access to administrative functions involving data persistence. Input sanitization libraries should be utilized consistently across all user-facing forms to prevent injection attacks at the source code level. Furthermore, implementing a Content Security Policy (CSP) header can mitigate the impact of any successful XSS attempts by restricting the sources from which scripts are allowed to load and execute, thereby reducing the effectiveness of injected payloads even if they bypass input filters. Regular security audits and penetration testing focused on web application logic flaws will help identify similar vulnerabilities before they can be exploited in production environments.