CVE-2018-14836 in Subrion CMS
Summary
by MITRE
Subrion 4.2.1 is vulnerable to Improper Access control because user groups not having access to the Admin panel are able to access it (but not perform actions) if the Guests user group has access to the Admin panel.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 04/29/2023
The vulnerability identified as CVE-2018-14836 affects Subrion version 4.2.1 and represents a critical improper access control flaw that undermines the application's security model. This vulnerability stems from a flawed permission architecture where the system fails to properly enforce access restrictions between different user groups, creating an unintended pathway for unauthorized users to gain visibility into administrative interfaces. The issue specifically manifests when the Guests user group is granted access to the Admin panel, allowing user groups that should be restricted from accessing administrative functionality to view the admin interface itself, though they cannot execute actions within it.
This access control bypass occurs due to inadequate validation of user permissions at the application level, where the system does not properly verify whether a user group has explicit authorization to access administrative functions. The vulnerability can be categorized under CWE-285 Improper Authorization, which specifically addresses situations where the application fails to properly enforce access controls. The flaw demonstrates a fundamental breakdown in the principle of least privilege, where users who should only have guest-level access are able to observe administrative interfaces, potentially exposing sensitive information about the application's structure and functionality.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with valuable reconnaissance data about the application's administrative interface structure. Even though the affected user groups cannot perform actions within the admin panel, the mere ability to access the interface provides attackers with insights into the system's architecture, available administrative functions, and potential attack vectors. This information can be leveraged in subsequent attacks, including social engineering attempts or targeted exploitation of other vulnerabilities within the administrative interface.
From an ATT&CK framework perspective, this vulnerability aligns with T1068 Access to Administrative Tools and T1087 Account Discovery, as it provides unauthorized access to administrative interfaces and reveals information about user group permissions. The vulnerability also relates to T1566 Phishing and T1078 Valid Accounts, as attackers could potentially use the discovered administrative access patterns to craft more effective social engineering campaigns or identify valid administrative accounts. Organizations using Subrion 4.2.1 should immediately implement mitigations including restricting guest user group permissions, implementing proper role-based access controls, and conducting comprehensive security audits of user group configurations.
The recommended remediation approach involves updating to a patched version of Subrion that properly implements access control mechanisms, ensuring that user groups cannot access administrative interfaces without explicit authorization. Additionally, administrators should review and tighten user group permissions, particularly for the Guests group, to prevent unauthorized access to administrative functionality. The vulnerability highlights the importance of implementing proper access control validation at multiple levels within web applications, including both authentication and authorization checks, to prevent similar issues from occurring in other components of the system.