CVE-2026-55570 — CRITICAL (9.0)

Vulnerability Description

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. Because the attribute is single-quoted and the value is produced with JSON.stringify() (which does not escape ', <, or >), a package whose name contains a single quote breaks out of the attribute and injects arbitrary HTML. In the desktop client the main BrowserWindow runs with nodeIntegration: true, contextIsolation: false, so the injected markup escalates from DOM XSS to arbitrary OS command execution. This is the same root cause and same impact as the original advisory, reached through a sibling sink the patch did not cover. This vulnerability is fixed in 3.7.0.

CVSS Score

9.0

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality

HIGH

Integrity

HIGH

Availability

HIGH

Related Weaknesses (CWE)

CWE-116 CWE-79 CWE-94

References

FAQ

What is CVE-2026-55570?

CVE-2026-55570 is a vulnerability with a CVSS score of 9.0 (CRITICAL). 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 H...

How severe is CVE-2026-55570?

CVE-2026-55570 has been rated CRITICAL with a CVSS base score of 9.0/10. This is considered a critical vulnerability requiring immediate attention.

Is there a patch for CVE-2026-55570?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.