8.8High

CVE-2026-93922

SiYuan through 3.8.4 renders notebook names as raw HTML in the Daily Note picker dialog without escaping, allowing stored cross-site scripting in the Electron renderer. Attackers can create notebooks with HTML payloads in names that execute JavaScript with Node.js access when the picker opens, enabling operating system command execution.

What this means for your business

  • An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.

What to do

  1. 1Ask your IT team or provider whether any of your systems use the affected product.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
8.8 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS v4
8.6
Weakness
CWE-79
Assigned by
disclosure@vulncheck.com

Dates

Published
2026-09-19
Last modified
2026-09-19
Sources
NVD

References