SiYuan: Stored XSS to RCE via Unsanitized Attribute View Asset Cell Content

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.9 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS

• CVE-2026-50551: 0.56% estimated exploitation activity in the next 30 days; percentile 46.70 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

SiYuan v3.6.5 and earlier versions contain a stored cross-site scripting (XSS) vulnerability in the Attribute View (database) asset cell renderer that escalates to remote code execution (RCE) in the Electron desktop client. This is a neighbor-bug of CVE-2026-44588: the fix for -44588 used escapeAriaLabel() (double-escapes <), but the AV asset renderers were left using the weaker escapeAttr() (escapes only quotes) or no escaping at all.

Vulnerability Details The Electron renderer is configured with nodeIntegration: true and contextIsolation: false (app/electron/main.js:307), allowing any JavaScript executing in the renderer to directly access Node.js APIs including require('childprocess'). Two XSS sinks exist.

Sink 1 (Direct Stored XSS - triggers on page load) app/src/protyle/render/av/cell.ts:1008: text += <span class="b3-chip avcelltext--url ariaLabel" aria-label="${escapeAttr(item.content)}" data-name="${escapeAttr(item.name)}"…

Published by the source

10 Jul 2026, 20:37 UTC

Last modified by the source

10 Jul 2026, 20:37 UTC

Source last checked

26 Oct 2026, 15:24 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-56mp-4f3v-fgj2

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# Patch Next advisory brief: CVE-2026-50551

Advisory: SiYuan: Stored XSS to RCE via Unsanitized Attribute View Asset Cell Content
IDs: CVE-2026-50551, GHSA-56mp-4f3v-fgj2
Record: https://patchnext.com/advisories/cve-2026-50551 (revision 1, source checked 26 Oct 2026, 15:24 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/siyuan-note/siyuan/kernel 0.0.0-20260628153353-2d5d72223df4. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/siyuan-note/siyuan/kernel: affected < 0.0.0-20260628153353-2d5d72223df4; fixed in 0.0.0-20260628153353-2d5d72223df4

## Suggested inspection (read-only)
- Go github.com/siyuan-note/siyuan/kernel: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/siyuan-note/siyuan/kernel.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-56mp-4f3v-fgj2 (GitHub-reviewed advisory GHSA-56mp-4f3v-fgj2 lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <0.0.0-20260628153353-2d5d72223df4)

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