CVE-2022-27331 in Zammad
Summary
by MITRE • 04/27/2022
An access control issue in Zammad v5.0.3 broadcasts administrative configuration changes to all users who have an active application instance, including settings that should only be visible to authenticated users.
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Analysis
by VulDB Data Team • 04/30/2022
The vulnerability identified as CVE-2022-27331 represents a critical access control flaw within the Zammad collaboration platform version 5.0.3. This issue fundamentally undermines the application's security model by allowing unauthorized information disclosure through improper privilege management. The flaw exists in the application's broadcast mechanism that handles administrative configuration changes, where the system fails to properly validate user permissions before disseminating sensitive settings to all connected users. This misconfiguration creates a scenario where any authenticated user can potentially access administrative-level configuration data that should remain restricted to authorized administrators only.
The technical root cause of this vulnerability stems from inadequate input validation and privilege checking within the Zammad application's communication layer. When administrative configuration changes are made, the system broadcasts these updates to all active application instances without performing proper authentication checks or role-based access controls. This behavior violates fundamental security principles and creates a pathway for privilege escalation through information disclosure. The flaw operates at the application logic level, where the system assumes all connected users have equal access to configuration data regardless of their actual authorization status. This issue aligns with CWE-284, which addresses improper access control mechanisms, and specifically demonstrates weaknesses in authorization enforcement within web applications.
The operational impact of this vulnerability extends beyond simple information disclosure to potentially enable more sophisticated attacks within the Zammad environment. Attackers who gain access to administrative configuration data could potentially identify system vulnerabilities, understand application architecture, and exploit other weaknesses in the platform. The broadcast mechanism creates a persistent risk where configuration changes remain accessible to all users throughout their session, providing attackers with extended opportunities to gather sensitive information. This vulnerability particularly affects organizations relying on Zammad for customer service management, as administrative settings may contain system credentials, integration endpoints, and other sensitive operational data that could be leveraged for further attacks. The risk is compounded by the fact that this affects all users with active application instances, making it difficult to contain and monitor.
Organizations should implement immediate mitigations including updating to patched versions of Zammad where available, implementing additional network-level access controls, and monitoring for unauthorized access patterns. Security teams should review and restrict user permissions within the application, ensuring that only authorized administrators have access to sensitive configuration settings. Network segmentation and monitoring solutions should be deployed to detect unusual data access patterns that might indicate exploitation of this vulnerability. The ATT&CK framework categorizes this issue under T1078 for valid accounts and T1566 for malicious file execution, as attackers could potentially use the disclosed information to craft more targeted attacks. Additionally, implementing proper logging and audit trails for administrative configuration changes will help detect unauthorized access attempts and provide forensic evidence for security incident response. Organizations should also consider implementing zero-trust network access controls and regularly reviewing user access permissions to prevent similar issues in other applications.