CVE-2026-73042 in SiYuan
Summary
by MITRE • 08/16/2026
SiYuan before v3.7.4 fails to properly escape database menu metadata in HTML interpolation, allowing stored values to execute script when users open group, view, or field-edit menus. Attackers can inject markup through field descriptions or names that close containing elements and execute arbitrary code via event handlers, reaching Node built-ins due to Electron's insecure configuration.
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Analysis
by VulDB Data Team • 08/16/2026
This vulnerability exists in SiYuan versions prior to 3.7.4 where the application fails to properly sanitize database menu metadata before incorporating it into HTML interpolation contexts. The flaw manifests when users interact with group, view, or field-edit menus, creating opportunities for stored cross-site scripting attacks through carefully crafted input values. The root cause lies in insufficient output escaping mechanisms that allow maliciously formatted data to be rendered directly into HTML without proper sanitization.
The technical implementation of this vulnerability stems from improper handling of user-controllable metadata within the application's Electron-based interface. When attackers provide field descriptions or names containing specially crafted markup, they can manipulate the HTML structure by closing existing elements and injecting new ones with event handlers. This creates a path for arbitrary code execution through the Electron framework's insecure default configuration that exposes Node.js built-ins to the renderer process. The vulnerability specifically targets the HTML interpolation mechanism where database metadata values are directly embedded into the user interface without adequate sanitization.
The operational impact of this vulnerability is significant as it allows remote attackers to execute arbitrary code on affected systems with the privileges of the application user. This creates a persistent threat vector that can be exploited through legitimate user interactions with database menus, making detection and prevention challenging. The attack requires no special privileges beyond normal application usage and can be delivered through stored data inputs that appear benign to users. Once successfully exploited, attackers gain access to Node.js built-ins within the Electron environment, potentially enabling full system compromise.
Mitigation strategies should focus on implementing comprehensive input validation and output escaping mechanisms for all user-controllable metadata values used in HTML interpolation contexts. The application must sanitize all database menu metadata before rendering it into HTML elements, employing proper context-aware escaping techniques that prevent script execution. Organizations should upgrade to SiYuan version 3.7.4 or later where this vulnerability has been addressed through improved sanitization of menu metadata. Additionally, security configurations should be reviewed to ensure Electron's Node.js integration is properly restricted and that automatic sandboxing mechanisms are enabled. This vulnerability aligns with CWE-79 (Cross-site Scripting) and maps to ATT&CK techniques involving code injection and privilege escalation through compromised applications.