CVE-2026-59834 in SiYuan
Summary
by MITRE • 07/10/2026
SiYuan is an open-source personal knowledge management system. Prior to 3.7.1, the block search endpoint POST /api/search/fullTextSearchBlock concatenates attacker-controlled paths values into SQL predicates used by non-SQL search modes, allowing an unauthenticated publish visitor to inject a UNION SELECT and return rows from hidden documents by projecting an allowed visible box and path. This issue is fixed in versions 3.7.1.
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Analysis
by VulDB Data Team • 07/10/2026
The vulnerability exists within SiYuan's block search functionality where the POST endpoint /api/search/fullTextSearchBlock fails to properly sanitize user input when constructing SQL predicates for non-SQL search modes. This represents a classic sql injection flaw that affects the system's database query construction process and allows attackers to manipulate the underlying data retrieval mechanisms through crafted input parameters.
The technical implementation of this vulnerability occurs when attacker-controlled path values are directly concatenated into SQL predicates without proper input validation or parameterization. The specific attack vector involves an unauthenticated user who can submit malicious input through the search endpoint, enabling them to inject UNION SELECT statements that bypass normal access controls. This allows unauthorized access to hidden documents that would normally be restricted from view by standard visibility permissions.
The operational impact of this vulnerability is significant as it undermines the core security model of the personal knowledge management system. An attacker can exploit this weakness to extract sensitive data from hidden documents without proper authentication or authorization, effectively bypassing the system's access control mechanisms. The vulnerability particularly affects systems where content visibility is controlled through document permissions and path-based access restrictions.
This vulnerability aligns with CWE-89 which specifically addresses SQL injection flaws in software applications that fail to properly sanitize user input before incorporating it into database queries. The attack pattern demonstrates characteristics consistent with the ATT&CK technique T1071.004 for application layer protocol manipulation, where an attacker exploits a weakness in data processing to gain unauthorized access to protected information.
The fix implemented in version 3.7.1 addresses this issue by properly sanitizing or parameterizing the path values before incorporating them into SQL predicates, ensuring that user input cannot be interpreted as part of the database query structure. This remediation approach follows established security best practices for preventing sql injection attacks and maintaining proper input validation throughout the application's data processing pipeline.
Organizations using SiYuan should prioritize upgrading to version 3.7.1 or later to address this vulnerability, as the exposure allows for unauthorized data access that could compromise sensitive personal information stored within the knowledge management system. The vulnerability represents a critical security risk that requires immediate attention given its potential to expose confidential content through simple search parameter manipulation.