CVE-2026-75916

Description

SiYuan through 3.7.3 contains a cross-site scripting vulnerability in the -((- block-reference autocomplete hint popup. In genHintItemHTML() (app/src/protyle/hint/extend.ts), a candidate block-s name, alias, and memo fields are concatenated into the popup-s HTML without escaping. An attacker who can set these metadata fields on a block can inject a self-firing payload (e.g. <img src=x onerror=...>) that executes automatically when a victim types -((- followed by a search term that surfaces the crafted block. Because SiYuan-s Electron windows run with nodeIntegration enabled, contextIsolation disabled, and no CSP, the injected script gains require(-child_process-) access, allowing the XSS to escalate to arbitrary OS command execution.