Description
SiYuan before v3.8.4 does not HTML-escape stored flashcard block content before interpolating it into the card-manager list markup. Block content returned by /api/riff/getRiffCards is inserted into a card item template in app/src/card/viewCards.ts and assigned to listElement.innerHTML, so content such as <img src=invalid onerror=...> becomes an executable event-handler attribute. Because the SiYuan desktop (Electron) main window is created with nodeIntegration enabled and contextIsolation disabled, an administrator who opens the card manager on a workspace containing attacker-supplied flashcard content (for example introduced through contribution or import) executes the attacker's script in a privileged renderer, which can lead to arbitrary code execution on the host. The affected endpoint remains behind authentication and administrator-role checks; this is an untrusted-content-to-privileged-renderer issue, not an authorization bypass.
Published: 2026-09-26
Score: 8.6 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Sat, 26 Sep 2026 13:30:00 +0000

Type Values Removed Values Added
Description SiYuan before v3.8.4 does not HTML-escape stored flashcard block content before interpolating it into the card-manager list markup. Block content returned by /api/riff/getRiffCards is inserted into a card item template in app/src/card/viewCards.ts and assigned to listElement.innerHTML, so content such as <img src=invalid onerror=...> becomes an executable event-handler attribute. Because the SiYuan desktop (Electron) main window is created with nodeIntegration enabled and contextIsolation disabled, an administrator who opens the card manager on a workspace containing attacker-supplied flashcard content (for example introduced through contribution or import) executes the attacker's script in a privileged renderer, which can lead to arbitrary code execution on the host. The affected endpoint remains behind authentication and administrator-role checks; this is an untrusted-content-to-privileged-renderer issue, not an authorization bypass.
Title SiYuan before v3.8.4 Stored XSS via Unescaped Flashcard Content
First Time appeared B3log
B3log siyuan
Weaknesses CWE-79
CPEs cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*
Vendors & Products B3log
B3log siyuan
References
Metrics cvssV3_1

{'score': 8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H'}

cvssV4_0

{'score': 8.6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}

Subscriptions

B3log Siyuan
cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-09-26T13:23:13.957Z

Reserved: 2026-09-26T02:32:35.659Z

Link: CVE-2026-100641

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Deferred

Published: 2026-09-26T14:16:46.080

Modified: 2026-09-26T14:16:46.193

Link: CVE-2026-100641

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-26T15:15:13Z

Weaknesses
  • CWE-79

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')