CRITICAL: CVE-2026-54158 (CVSS 9.9) — multiple products

CVE: CVE-2026-54158

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

Severity: CRITICAL

Status: Critical advisory

Affected

_See vendor advisory_

Summary

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, the attribute-view (database) cell renderer genAVValueHTML interpolates cell content raw in four of its branches: text, url, phone, and mAsset. A cell value like </textarea><img src=x onerror="..."> or "><img src=x onerror="..."> breaks out of its surrounding tag and runs arbitrary JavaScript in the renderer when the victim opens the block-attribute panel. On Electron desktop the renderer runs with nodeIntegration:true, so the XSS chains to host RCE via require('child_process'). AV files live under the workspace and ride normal sync, so an attacker with write access to any synced workspace plants the payload once and it fires on every device that opens a panel containing that row.he kernel doesn't escape on the way in either, so the malicious cell persists byte-for-byte. There's no equivalent of the html.EscapeAttrVal call that protects block IAL attributes at kernel/model/blockial.go:261. This vulnerability is fixed in 3.7.0.

Verified Sources

• NVD entry
• GitHub Advisory
• MITRE

References

• https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5xfx-xj4h-5p7r

_Validated by the Lyrie Threat Intelligence Pipeline — 3 independent sources confirmed before publication. No speculation._