CVE-2026-55570: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
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.
AI Analysis
Technical Summary
CVE-2026-55570 describes a critical improper neutralization of input vulnerability (CWE-79) in SiYuan versions before 3.7.0. The vulnerability occurs because untrusted metadata fields are serialized into a single-quoted HTML attribute without escaping characters like single quotes, less-than, or greater-than signs. This allows a malicious package name containing a single quote to break out of the attribute context and inject arbitrary HTML. Due to the desktop client's configuration (nodeIntegration: true, contextIsolation: false), this DOM-based XSS can escalate to arbitrary OS command execution. The issue shares the same root cause and impact as a previous advisory but affects a sibling sink that was not covered by the prior patch. The vulnerability is resolved in SiYuan 3.7.0.
Potential Impact
Successful exploitation allows an attacker to inject arbitrary HTML and escalate from DOM-based cross-site scripting to arbitrary operating system command execution on the victim's machine running the SiYuan desktop client. This leads to full compromise of the affected system. The vulnerability has a CVSS 3.1 score of 9.0 (critical), reflecting its high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
This vulnerability is fixed in SiYuan version 3.7.0. Users should upgrade to version 3.7.0 or later to remediate this issue. No other mitigation or temporary workaround is indicated in the available data.
CVE-2026-55570: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in siyuan-note siyuan
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 v3.1
Score 9.0critical
Affected software
pkg:github/siyuan-note/siyuanRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-55570 describes a critical improper neutralization of input vulnerability (CWE-79) in SiYuan versions before 3.7.0. The vulnerability occurs because untrusted metadata fields are serialized into a single-quoted HTML attribute without escaping characters like single quotes, less-than, or greater-than signs. This allows a malicious package name containing a single quote to break out of the attribute context and inject arbitrary HTML. Due to the desktop client's configuration (nodeIntegration: true, contextIsolation: false), this DOM-based XSS can escalate to arbitrary OS command execution. The issue shares the same root cause and impact as a previous advisory but affects a sibling sink that was not covered by the prior patch. The vulnerability is resolved in SiYuan 3.7.0.
Potential Impact
Successful exploitation allows an attacker to inject arbitrary HTML and escalate from DOM-based cross-site scripting to arbitrary operating system command execution on the victim's machine running the SiYuan desktop client. This leads to full compromise of the affected system. The vulnerability has a CVSS 3.1 score of 9.0 (critical), reflecting its high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
This vulnerability is fixed in SiYuan version 3.7.0. Users should upgrade to version 3.7.0 or later to remediate this issue. No other mitigation or temporary workaround is indicated in the available data.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-16T23:11:20.214Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3c501e4853345fc1e45c5d
Added to database: 06/24/2026, 21:46:06 UTC
Last enriched: 07/01/2026, 22:42:08 UTC
Last updated: 08/08/2026, 12:41:11 UTC
Views: 125
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