CVE-2022-22682 in Calendar
Summary
by MITRE • 07/12/2022
Improper neutralization of input during web page generation ('Cross-site Scripting') vulnerability in Event Management in Synology Calendar before 2.4.5-10930 allows remote authenticated users to inject arbitrary web script or HTML via unspecified vectors.
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Analysis
by VulDB Data Team • 07/21/2022
The CVE-2022-22682 vulnerability represents a critical cross-site scripting flaw within Synology Calendar's event management functionality, specifically affecting versions prior to 2.4.5-10930. This vulnerability resides in the web page generation process where input validation and sanitization mechanisms fail to properly neutralize user-supplied data before rendering it within web interfaces. The flaw enables authenticated attackers to inject malicious scripts or HTML content that can be executed in the context of other users' browsers, creating a persistent security risk within the calendar application's web interface. The vulnerability's classification as improper input neutralization aligns with CWE-79, which specifically addresses cross-site scripting conditions where web applications fail to properly sanitize user input before incorporating it into dynamically generated web content.
The technical exploitation of this vulnerability occurs through unspecified vectors within the calendar event management system, where authenticated users can submit crafted input that bypasses existing security controls. When the calendar application processes these inputs during web page generation, it fails to adequately escape or encode special characters that could be interpreted as HTML or JavaScript commands. This oversight allows attackers to inject malicious payloads that execute in the browser context of other users who view the affected calendar entries. The authentication requirement means that attackers must first establish valid credentials to exploit this vulnerability, but once authenticated, they can manipulate calendar events to deliver malicious content to other users within the same calendar instance.
The operational impact of CVE-2022-22682 extends beyond simple script injection, as it can enable more sophisticated attacks including session hijacking, credential theft, and data exfiltration. When malicious scripts execute in victim browsers, they can access cookies, localStorage, and other browser resources that may contain sensitive information or session tokens. This vulnerability particularly affects collaborative calendar environments where multiple users share event data, as a single compromised event can serve as a vector for broader network compromise. The attack surface is amplified in enterprise environments where Synology Calendar serves as a central scheduling tool, potentially allowing attackers to escalate privileges or gain unauthorized access to additional system resources through the compromised calendar interface.
Mitigation strategies for this vulnerability primarily focus on immediate software updates to version 2.4.5-10930 or later, which contain the necessary patches to properly neutralize input during web page generation. Organizations should implement comprehensive input validation and output encoding mechanisms that align with OWASP secure coding practices, ensuring that all user-supplied data is properly sanitized before being rendered in web interfaces. Network monitoring should be enhanced to detect anomalous script injection patterns within calendar applications, while security teams should conduct regular vulnerability assessments focusing on web application input handling. Additionally, implementing content security policies and disabling unnecessary script execution in calendar applications can provide defense-in-depth measures that reduce the impact of potential exploitation attempts. The vulnerability's alignment with ATT&CK technique T1059.007 for scripting languages highlights the importance of monitoring for malicious script execution patterns that could indicate exploitation of this XSS vulnerability.