XSS in Siyuan-Note Siyuan

CVE-2026-73053

SiYuan versions before v3.7.4 contain a cross-site scripting vulnerability in the unicode2Emoji function that fails to sanitize codepoint branch output. Attackers can craft document icons with hex-encoded markup that executes in the renderer with Node integration enabled, achieving arbitrary code execution on the host system.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (41.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 41.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-73053: held from 0.003 to 0.005.

EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-73053?
CVE-2026-73053 is a critical-severity vulnerability in Siyuan-Note Siyuan, classified under Cross-site Scripting. CVSS score: 9.0/10. Published 2026-08-15.
How severe is CVE-2026-73053?
Critical severity. CVSS v3 base score is 9.0 out of 10.