CVE-2026-44588

SiYuan: URL-encoded title bypasses `escapeAriaLabel`, decoded by `decodeURIComponent` into a tooltip-XSS

State
Published
Severity
9.4 Critical
Published
May 14, 2026
Updated
May 15, 2026
Reserved
May 6, 2026

Read the record on cve.org

Description

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, he tooltip mouseover handler in app/src/block/popover.ts reads aria-label via getAttribute and passes it through decodeURIComponent before assigning to messageElement.innerHTML in app/src/dialog/tooltip.ts:41. The encoder used at the producer side, escapeAriaLabel in app/src/util/escape.ts:19-25, only handles HTML special characters (", ', <, literal &lt;) — it leaves %XX URL-escapes untouched. So a doc title containing %3Cimg src=x onerror=...%3E round-trips through escapeAriaLabel and the HTML attribute layer unmodified. Then decodeURIComponent on the consumer side converts %3C to a literal < character (a real <, NOT a character reference). When that string is assigned to innerHTML, the HTML5 tokenizer enters TagOpenState on the literal <, parses the <img> element, and the onerror handler fires. Because the renderer runs with nodeIntegration: true, contextIsolation: false, webSecurity: false (app/electron/main.js:407-411), require('child_process') is reachable from the injected handler, escalating to arbitrary code execution.This vulnerability is fixed in 3.7.0.

Scores

CVSSScoreVectorSource
4.09.4 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:HGitHub_M

Weaknesses

  • CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-116 Improper Encoding or Escaping of Output
  • CWE-1188 Insecure Default Initialization of Resource

Affected Products

ProductVersions
siyuansiyuan-note
  • < 3.7.0Affected

References

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