CVE-2026-54070

HIGH
MEDIUM Priority: 0.02 BB Relevance: 54/100
Published: 2026-06-24 Modified: 2026-10-25 First seen: 2026-10-29 Status: active

Attack Surface

Network No Auth Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: High
PR: None
UI: Required
S: Unchanged
C: High
I: High
A: Low

Description

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, renderPackageREADME in kernel/bazaar/readme.go renders a Bazaar package README from Markdown to HTML with the lute engine and SetSanitize(true). The lute sanitizer is an event-handler blocklist: allowAttr rejects only attribute names present in a fixed eventAttrs map copied from the w3schools legacy handler list. That map omits modern event handlers. onpointerover, onpointerdown, onauxclick, onbeforetoggle, onfocusin, onanimationstart, and ontransitionend are not in the list, so the sanitizer passes them through verbatim on any tag. The frontend assigns the rendered HTML to mdElement.innerHTML in app/src/config/bazaar.ts with no client-side DOMPurify on this path, into a normal element in the main document (no iframe, no sandbox). The kernel sends no Content-Security-Policy, X-Frame-Options, or X-Content-Type-Options header on any response, so an inline handler runs when its event fires. The README is rendered when an Administrator opens a package in Settings → Marketplace, after the one-time marketplace trust consent. Install is not required. Result: a third-party Bazaar package author runs JavaScript in the Administrator's authenticated SiYuan origin when the Administrator views and interacts with the package listing, and gains full control of the workspace. This vulnerability is fixed in 3.7.0.

Weakness Classification (2)

Bug Bounty Relevance

54 / 100
✓ Network accessible
✓ No authentication

CVSS Score

7.1 / 10.0 v3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:L

EPSS — Exploitation Probability

0.30%
Raw Score 0.003000
Percentile 22.7%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00300
2026-10-28
0.00300

Intelligence Sources

nvd ref →