CVE-2016-4873 in Cybozu Office
Summary
by MITRE
The "Project" function in Cybozu Office 9.0.0 through 10.4.0 does not properly check access permissions, which allows remote authenticated users to alter project information.
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Analysis
by VulDB Data Team • 08/31/2020
The vulnerability identified as CVE-2016-4873 resides within the Project function of Cybozu Office software versions 9.0.0 through 10.4.0, representing a critical access control flaw that undermines the security posture of organizations relying on this collaboration platform. This issue manifests as a failure in proper access permission validation, creating a pathway for authenticated attackers to manipulate project data without appropriate authorization. The vulnerability affects a wide range of business collaboration environments where project management features are utilized, potentially exposing sensitive organizational information to unauthorized modifications.
The technical implementation of this flaw demonstrates a classic insufficient authorization check pattern that aligns with CWE-285, which specifically addresses improper authorization within software systems. The vulnerability occurs when the application fails to validate user permissions before allowing modifications to project-related data structures, enabling authenticated users to bypass intended access controls. This weakness exists at the application logic level where the system should verify user credentials and privileges against the specific project resources being accessed, but instead permits arbitrary alterations regardless of user role or assigned permissions.
From an operational impact perspective, this vulnerability creates significant risks for organizations using Cybozu Office for project management and collaboration. Attackers with legitimate login credentials can potentially alter project timelines, budgets, resource allocations, and other critical project parameters without detection. The implications extend beyond simple data modification to include potential business disruption, compliance violations, and loss of trust in organizational collaboration systems. The vulnerability is particularly dangerous in environments where project data integrity is paramount for business operations, regulatory compliance, or stakeholder confidence, as unauthorized changes could lead to cascading effects throughout project execution and reporting.
The attack vector for this vulnerability requires only authenticated access, making it particularly concerning as it can be exploited by users with legitimate but potentially compromised accounts or by malicious insiders. This aligns with ATT&CK technique T1078 which covers legitimate credentials usage for persistence and privilege escalation. Organizations should consider implementing additional monitoring and audit controls around project modification activities to detect unauthorized changes. The vulnerability also highlights the importance of proper input validation and access control implementation, particularly in collaborative environments where multiple users require different levels of access to shared resources. Security practitioners should prioritize patch management for affected versions and consider implementing network segmentation to limit the potential impact of credential compromise within the Cybozu Office environment.
Mitigation strategies should include immediate deployment of vendor-provided patches or updates addressing the access control validation issue, along with enhanced monitoring of project-related activities and access logs. Organizations should implement principle of least privilege configurations, ensuring that users only receive the minimum permissions necessary for their roles within the project management system. Regular security assessments of collaboration platforms should include thorough testing of access control mechanisms to prevent similar vulnerabilities from emerging in other components of the system. The vulnerability serves as a reminder of the critical importance of proper authorization checking in enterprise collaboration tools, particularly those handling sensitive business data and project information that requires integrity and confidentiality protection.