What is CVE-2026-82654?

CVE-2026-82654 is a high-severity vulnerability in Siyuan-Note Siyuan, classified under Cross-site Scripting. CVSS score: 8.9/10. Published 2026-08-30.

How severe is CVE-2026-82654?

High severity. CVSS v3 base score is 8.9 out of 10.

XSS in Siyuan-Note Siyuan

CVE-2026-82654

SiYuan before v3.8.1 fails to properly escape block name, alias, and memo fields in hint, backlink, and breadcrumb rendering functions. Attackers can set a block's name to contain HTML/script tags that execute when another user views documents referencing or displaying that block.

Vulnerability class: XSS (Cross-Site Scripting)

CVSS v3 metric

CVSS v3 base score 8.9 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L.

Affected products

Siyuan-note Siyuan

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

disclosure@vulncheck.com (vendor-advisory)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-82654?: CVE-2026-82654 is a high-severity vulnerability in Siyuan-Note Siyuan, classified under Cross-site Scripting. CVSS score: 8.9/10. Published 2026-08-30.
How severe is CVE-2026-82654?: High severity. CVSS v3 base score is 8.9 out of 10.