CVE-2026-100640: Exposure of Sensitive Information to an Unauthorized Actor in siyuan-note siyuan
SiYuan before v3.8.4 contains an authorization omission in the siyuan-get IPC handler that allows remote-kernel renderers to access native clipboard formats by invoking clipboardReadMathML, clipboardReadOffice, and clipboardReadWPS commands with matching plaintext. Attackers controlling remote renderer content can obtain MathML formulas, Office bytes, and WPS bytes from local clipboard during user-mediated paste operations.
AI Analysis
Technical Summary
CVE-2026-100640 is an authorization omission vulnerability in SiYuan note-taking software prior to version 3.8.4. The vulnerability exists in the siyuan-get IPC handler, which improperly authorizes remote-kernel renderers to invoke clipboardReadMathML, clipboardReadOffice, and clipboardReadWPS commands. This allows attackers controlling remote renderer content to access native clipboard formats including MathML, Office, and WPS data during user-mediated paste operations, exposing sensitive information from the local clipboard.
Potential Impact
An attacker who controls remote renderer content can access sensitive clipboard data formats without proper authorization. This exposure can lead to leakage of potentially sensitive MathML formulas and document data from Office and WPS formats. The vulnerability requires user interaction (paste operation) and local access to the clipboard, but no privileges or user authentication are required to exploit the flaw remotely.
Mitigation Recommendations
A fix is available in SiYuan version 3.8.4. Users should upgrade to version 3.8.4 or later to remediate this vulnerability. Until patched, restricting untrusted remote renderer content and avoiding paste operations from untrusted sources can reduce risk.
CVE-2026-100640: Exposure of Sensitive Information to an Unauthorized Actor in siyuan-note siyuan
Description
SiYuan before v3.8.4 contains an authorization omission in the siyuan-get IPC handler that allows remote-kernel renderers to access native clipboard formats by invoking clipboardReadMathML, clipboardReadOffice, and clipboardReadWPS commands with matching plaintext. Attackers controlling remote renderer content can obtain MathML formulas, Office bytes, and WPS bytes from local clipboard during user-mediated paste operations.
CVSS v4.0
Score 8.6high
Affected software
siyuan-note
siyuan
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-2026-100640 is an authorization omission vulnerability in SiYuan note-taking software prior to version 3.8.4. The vulnerability exists in the siyuan-get IPC handler, which improperly authorizes remote-kernel renderers to invoke clipboardReadMathML, clipboardReadOffice, and clipboardReadWPS commands. This allows attackers controlling remote renderer content to access native clipboard formats including MathML, Office, and WPS data during user-mediated paste operations, exposing sensitive information from the local clipboard.
Potential Impact
An attacker who controls remote renderer content can access sensitive clipboard data formats without proper authorization. This exposure can lead to leakage of potentially sensitive MathML formulas and document data from Office and WPS formats. The vulnerability requires user interaction (paste operation) and local access to the clipboard, but no privileges or user authentication are required to exploit the flaw remotely.
Mitigation Recommendations
A fix is available in SiYuan version 3.8.4. Users should upgrade to version 3.8.4 or later to remediate this vulnerability. Until patched, restricting untrusted remote renderer content and avoiding paste operations from untrusted sources can reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-26T02:32:35.659Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ab7c9a5f7a7c5410652fd24
Added to database: 09/26/2026, 13:33:25 UTC
Last enriched: 09/26/2026, 14:03:56 UTC
Last updated: 09/27/2026, 04:31:30 UTC
Views: 13
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