CVE-2026-27012 in openstamanager
Summary
by MITRE • 03/04/2026
OpenSTAManager is an open source management software for technical assistance and invoicing. In 2.9.8 and earlier, a privilege escalation and authentication bypass vulnerability in OpenSTAManager allows any attacker to arbitrarily change a user's group (idgruppo) by directly calling modules/utenti/actions.php. This can promote an existing account (e.g. agent) into the Amministratori group as well as demote any user including existing administrators.
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Analysis
by VulDB Data Team • 03/04/2026
The vulnerability identified as CVE-2026-27012 affects OpenSTAManager version 2.9.8 and earlier, representing a critical privilege escalation and authentication bypass flaw that undermines the software's user access controls. This vulnerability resides within the application's user management module, specifically in the modules/utenti/actions.php file which handles user-related operations without proper authorization checks. The flaw allows unauthenticated or low-privileged attackers to manipulate user group assignments directly through API endpoints, creating a pathway for arbitrary privilege elevation that fundamentally compromises the system's security model.
The technical implementation of this vulnerability stems from insufficient input validation and access control mechanisms within the user management system. When attackers call the modules/utenti/actions.php endpoint, they can modify the idgruppo parameter associated with any user account, effectively allowing them to promote regular users to administrator privileges or demote existing administrators to lower privilege levels. This represents a classic case of insufficient authorization checks, where the application fails to verify whether the requesting entity has proper permissions to modify user group memberships. The vulnerability aligns with CWE-285, which addresses insufficient authorization in software systems, and specifically manifests as a weakness in access control enforcement.
The operational impact of this vulnerability is severe and far-reaching, as it enables attackers to completely subvert the application's user management security architecture. An attacker could elevate a standard agent account to administrator level, gaining complete control over the system including access to sensitive financial data, user management capabilities, and potentially the ability to create new administrative accounts. This privilege escalation capability allows for persistent access and makes the system vulnerable to data exfiltration, manipulation of invoicing records, and unauthorized technical assistance management. The vulnerability essentially renders the application's built-in access control mechanisms ineffective, creating a backdoor for unauthorized administrative access.
Organizations utilizing OpenSTAManager version 2.9.8 or earlier face significant risk exposure due to this vulnerability, particularly in environments where the software manages sensitive technical assistance and invoicing data. The attack surface is broad as the vulnerability can be exploited remotely without requiring prior authentication, making it particularly dangerous for web-facing installations. Security teams should consider this vulnerability as part of the ATT&CK framework's privilege escalation techniques, specifically mapping it to T1078 which covers valid accounts and T1548 which addresses abuse of privileges. The vulnerability also intersects with T1068, which covers exploit for privilege escalation, and T1566 which covers phishing and social engineering attacks that might be used to initially gain access to the system.
Mitigation strategies should focus on immediate patching of the OpenSTAManager application to version 2.9.9 or later, which contains the necessary fixes for this vulnerability. Additionally, organizations should implement network segmentation to limit access to the affected application, enforce strong authentication mechanisms, and conduct thorough access control reviews. Security monitoring should be enhanced to detect unusual user group modifications, and regular security assessments should be performed to identify similar vulnerabilities in the application's codebase. The fix should include proper authorization checks that verify user permissions before allowing group membership modifications, ensuring that only authorized administrators can perform such operations. Organizations should also consider implementing role-based access controls and regular security audits to prevent similar issues in other components of their technical assistance and invoicing infrastructure.