CVE-2024-39817 in Office
Summary
by MITRE • 08/06/2024
Insertion of sensitive information into sent data issue exists in Cybozu Office 10.0.0 to 10.8.6, which may allow a user who can login to the product to view data that the user does not have access by conducting 'search' under certain conditions in Custom App.
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Analysis
by VulDB Data Team • 09/12/2024
The vulnerability identified as CVE-2024-39817 represents a critical information disclosure flaw within Cybozu Office versions 10.0.0 through 10.8.6. This issue stems from improper handling of sensitive data during search operations within Custom App functionality, creating a scenario where authenticated users can potentially access information outside their designated access permissions. The vulnerability specifically manifests when users perform search operations under certain predetermined conditions, allowing them to retrieve data they should not logically be able to view based on their access controls.
This security weakness falls under the category of improper access control as classified by CWE-284, where the system fails to properly enforce access restrictions during data retrieval operations. The technical implementation appears to have a flaw in the search query processing mechanism where sensitive data filtering does not adequately consider user permissions when constructing response data. The vulnerability exploits the interaction between authentication mechanisms and data access controls, particularly within the Custom App search functionality, where the system does not properly validate or filter search results based on the authenticated user's privilege levels.
The operational impact of this vulnerability extends beyond simple data exposure, as it represents a fundamental breakdown in the application's security model. An attacker with valid login credentials can leverage this flaw to conduct unauthorized data reconnaissance and potentially access confidential information belonging to other users within the same system. This could lead to significant data breaches, compliance violations, and potential escalation to more serious attacks if the exposed data includes sensitive user information, business intelligence, or system configuration details. The vulnerability is particularly concerning because it operates silently within normal user operations, making detection difficult and potentially allowing prolonged unauthorized access.
Mitigation strategies should focus on implementing comprehensive access control validation at the data retrieval layer, ensuring that all search operations properly filter results based on user permissions. Organizations should immediately update to the latest version of Cybozu Office where this vulnerability has been addressed, while also implementing additional monitoring of search operations and access patterns. The fix should include enhanced input validation and proper privilege checking mechanisms that prevent unauthorized data exposure during search operations. Security teams should also consider implementing network-level monitoring to detect anomalous search behaviors that might indicate exploitation attempts. This vulnerability aligns with ATT&CK technique T1078 for valid accounts and T1566 for credential harvesting, as it allows for unauthorized data access through legitimate user credentials.