What is CVE-2026-55570?

CVE-2026-55570 is a critical-severity vulnerability in Siyuan-note Siyuan, classified under Cross-site Scripting. CVSS score: 9.0/10. Published 2026-06-24.

How severe is CVE-2026-55570?

Critical severity. CVSS v3 base score is 9.0 out of 10.

RCE in Siyuan-note Siyuan

CVE-2026-55570

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, it does not escape the untrusted fields (name, version, author, description) when they are serialized into the data-obj HTML attribute of each marketplace card…

Vulnerability class: XSS (Cross-Site Scripting)

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.

Affected products

Siyuan-note Siyuan — versions < 3.7.0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting
CWE-94 — Code Injection
CWE-116 — Improper Encoding or Escaping of Output

References

security-advisories@github.com (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-55570?: CVE-2026-55570 is a critical-severity vulnerability in Siyuan-note Siyuan, classified under Cross-site Scripting. CVSS score: 9.0/10. Published 2026-06-24.
How severe is CVE-2026-55570?: Critical severity. CVSS v3 base score is 9.0 out of 10.