CVE-2018-11628 in Master Calendar
Summary
by MITRE
Data input into EMS Master Calendar before 8.0.0.201805210 via URL parameters is not properly sanitized, allowing malicious attackers to send a crafted URL for XSS.
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Analysis
by VulDB Data Team • 06/24/2024
The vulnerability described in CVE-2018-11628 represents a critical cross-site scripting flaw within the EMS Master Calendar application prior to version 8.0.0.201805210. This security weakness stems from inadequate input validation and sanitization mechanisms that process URL parameters containing user-supplied data. The vulnerability specifically affects the calendar application's handling of web requests where attackers can inject malicious scripts through crafted URL parameters, creating a persistent security risk for organizations relying on this system.
The technical flaw manifests when the application fails to properly sanitize or escape user-provided input before processing it within the web interface. This occurs at the input validation layer where the system does not adequately filter or encode special characters that could be interpreted as executable code by web browsers. The vulnerability operates under CWE-79 which specifically addresses Cross-Site Scripting flaws, where improper validation of input data allows attackers to inject malicious scripts that execute in the context of other users' browsers. When a victim clicks on a maliciously crafted URL containing XSS payload, the script executes in their browser session, potentially leading to session hijacking, credential theft, or further exploitation.
The operational impact of this vulnerability extends beyond simple script execution, as it creates a persistent threat vector that can be leveraged for various malicious activities. Attackers can craft URLs that inject malicious JavaScript code to steal session cookies, redirect users to phishing sites, or even modify calendar entries to spread additional malware. The vulnerability affects all users who interact with the calendar application through web interfaces, making it particularly dangerous in enterprise environments where calendar systems are widely used for scheduling and collaboration. This flaw can be exploited by attackers who gain access to the victim's browser session, potentially leading to unauthorized access to sensitive calendar data and associated business information.
Organizations should immediately implement multiple layers of mitigation strategies to address this vulnerability. The primary remediation involves updating the EMS Master Calendar application to version 8.0.0.201805210 or later, which includes proper input sanitization and output encoding mechanisms. Additionally, implementing proper URL parameter validation and sanitization within the application code can serve as a defensive measure. Network-level protections such as web application firewalls and content security policies should be deployed to detect and block suspicious URL patterns. Security teams should also conduct regular security assessments of web applications to identify similar input validation vulnerabilities and ensure proper implementation of the principle of least privilege. The mitigation approach aligns with ATT&CK technique T1059.007 which addresses script injection attacks, emphasizing the need for robust input validation and output encoding to prevent malicious code execution in web applications.