Cross-Site Scripting Vulnerabilities in SiYuan, Angular, and @leanprover/unicode-input-component
Multiple newly reported cross-site scripting (XSS) vulnerabilities affect unrelated software products, including SiYuan, Angular, and @leanprover/unicode-input-component. In SiYuan, incomplete SVG sanitization can let an unauthenticated attacker deliver a crafted URL that executes arbitrary JavaScript in the application's origin, enabling theft of session tokens, cookies, and API keys, as well as unauthorized access to notes, document contents, and configuration data. In Electron-based deployments, the impact may escalate to remote code execution if insecure web preferences such as nodeIntegration are enabled or contextIsolation is disabled.
Angular disclosed a separate XSS flaw, tracked as CVE-2026-32635, caused by a sanitization bypass involving internationalized security-sensitive attributes such as href when combined with untrusted data binding; fixed versions include 22.0.0-next.3, 21.2.4, 20.3.18, and 19.2.20. A third, distinct issue, CVE-2026-32732, affects @leanprover/unicode-input-component and allows arbitrary JavaScript execution in a victim's browser session, potentially enabling session abuse, data access, and unauthorized backend requests. These are separate vulnerability disclosures rather than a single coordinated incident, and the content is substantive security reporting rather than fluff.
Timeline
Apr 1, 2026
CVE-2026-34605 SiYuan reflected XSS disclosure published
A new SiYuan reflected cross-site scripting vulnerability, CVE-2026-34605, was publicly reported with high severity. The disclosure said attackers could execute JavaScript to steal session cookies and CSRF tokens, read or alter a victim’s knowledge base, delete workspaces, and potentially plant persistent XSS payloads.
Mar 20, 2026
SiYuan fixes XSS issue in version 3.6.1
SiYuan released version 3.6.1 to fix the SVG sanitization bypass and unsafe dynamic icon handling that enabled the XSS vulnerability. The patch addressed the incomplete prior remediation affecting version 3.6.0 and earlier.
Mar 20, 2026
SiYuan vulnerability assigned CVE-2026-32940 and linked to incomplete prior fix
The SiYuan XSS issue was documented as CVE-2026-32940 and described as an incomplete fix for CVE-2026-29183, with bypasses using data:text/xml or data:application/xml in SVG href attributes. Reporting clarified that exploitation was click-through and did not depend on img tag rendering.
Mar 17, 2026
Angular XSS vulnerability warning published by Belgium CCB
Belgium's Centre for Cybersecurity issued a public advisory warning about an XSS vulnerability in Angular and urged users to patch immediately. The reference does not provide further technical details in the supplied content.
Mar 17, 2026
SiYuan XSS affects version 3.6.0 and earlier
A reflected cross-site scripting vulnerability in SiYuan was identified in version 3.6.0 and earlier, caused by incomplete SVG sanitization and unsafe handling of user-controlled input in the unauthenticated /api/icon/getDynamicIcon endpoint. The flaw could let attackers execute JavaScript in the SiYuan origin if a victim opened a crafted URL or interacted with malicious SVG content.
Mar 16, 2026
CVE-2026-32732 XSS in @leanprover/unicode-input-component disclosed
A cross-site scripting vulnerability affecting @leanprover/unicode-input-component was publicly reported. The issue could allow arbitrary JavaScript execution in a victim's browser session, potentially enabling session theft, data access, and unauthorized backend requests using the victim's privileges.
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SiYuan Mermaid Rendering Flaws Expose NTLM Hashes and Enable Electron RCE
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2 weeks ago
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