CVE-2020-5582 in Garoon
Summary
by MITRE
Cybozu Garoon 4.0.0 to 5.0.1 allows remote authenticated attackers to bypass access restriction to alter the data for the file attached to Report via unspecified vectors.
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Analysis
by VulDB Data Team • 06/30/2020
The vulnerability identified as CVE-2020-5582 affects Cybozu Garoon versions 4.0.0 through 5.0.1, representing a critical access control flaw that undermines the security posture of this collaboration platform. This issue specifically targets the report functionality within the system, where authenticated attackers can exploit unspecified vectors to circumvent intended access restrictions. The vulnerability arises from insufficient validation mechanisms that should normally prevent unauthorized modification of file attachments linked to reports, creating a significant escalation path for malicious actors who already possess legitimate credentials.
The technical implementation of this flaw stems from inadequate input sanitization and access control validation within the file attachment processing pipeline for report objects. When users attempt to modify report data, particularly file attachments, the system fails to properly verify whether the authenticated user possesses the necessary permissions to perform such operations. This weakness allows attackers to manipulate the system's permission model through indirect means, potentially enabling data tampering, information disclosure, or even privilege escalation depending on the broader system architecture. The unspecified nature of the attack vectors suggests multiple potential exploitation pathways, including but not limited to parameter manipulation, session hijacking, or manipulation of internal access control lists.
The operational impact of this vulnerability extends beyond simple data integrity concerns, as it represents a fundamental breakdown in the application's security model that could enable sophisticated attacks. An attacker who successfully exploits this vulnerability could modify critical business data, inject malicious content into report attachments, or potentially access sensitive information that should remain restricted to authorized personnel only. This weakness particularly affects organizations relying on Garoon for document management and collaboration, where report integrity is paramount for business operations and regulatory compliance. The vulnerability's remote nature means that attackers do not require physical access to the system, and the authenticated requirement lowers the barrier to exploitation compared to fully unauthenticated attacks.
Organizations should immediately implement mitigations including thorough access control reviews, enhanced input validation procedures, and comprehensive code auditing of the report attachment functionality. The vulnerability aligns with CWE-285, which addresses improper authorization issues, and could potentially map to ATT&CK techniques involving privilege escalation and data manipulation. System administrators should consider implementing additional monitoring for report modification activities, especially around file attachment changes, and establish stricter audit trails for all data modification operations. Patch management procedures should be prioritized to ensure immediate deployment of vendor-provided fixes, while network segmentation and least-privilege access models can help minimize the potential impact if exploitation occurs. The vulnerability demonstrates the critical importance of maintaining robust access control mechanisms within collaborative platforms where users may have varying levels of authorization and where data integrity is essential for business operations.