Critical RCE in SiYuan Bazaar Lets Malicious Packages Run OS Commands
SiYuan disclosed CVE-2026-56395, a critical remote code execution flaw affecting versions before 3.6.1. The bug stems from improper sanitization of Bazaar marketplace package metadata and README content, allowing malicious package authors to inject arbitrary HTML and JavaScript into fields including displayName, description, and README.
When a user browses the Bazaar, the injected payload can trigger cross-site scripting and, because the Electron application has nodeIntegration enabled, escalate to execution of operating system commands on the victim device. The vulnerability has been rated critical, with reported scores of 9.6 CVSS v3.1 and 9.4 CVSS v4.0; remediation is to upgrade to SiYuan 3.6.1 or later and avoid installing packages from untrusted sources.
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2 events from the most recent confirmed update back to the earliest known activity.
CVE-2026-56395 is published for SiYuan Bazaar RCE
CVE-2026-56395 was published as a critical vulnerability affecting SiYuan versions before 3.6.1. The advisory described remote code execution through malicious Bazaar package metadata and README content and recommended upgrading to 3.6.1 or later.
SiYuan fixes Bazaar RCE issue in version 3.6.1
SiYuan resolved a remote code execution vulnerability caused by improper sanitization of Bazaar package metadata and README content in version 3.6.1. The flaw allowed malicious package authors to inject HTML and JavaScript that could lead to OS command execution via Electron nodeIntegration.
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CVE-2026-56395 - SiYuan - Remote Code Execution via Malicious Bazaar Package Metadata and README
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Open sourceSiYuan - Remote Code Execution via Malicious Bazaar Package Metadata and README | Advisories | VulnCheck
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Open sourceCVE-2026-56397 - SiYuan - Remote Code Execution via Malicious Bazaar Package Metadata and README
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