CVE-2026-100642: Origin Validation Error in siyuan-note siyuan
SiYuan versions from v2.1.0 before v3.8.4 contain a cross-site request forgery vulnerability in the CheckAuth lock-screen pass-through branch that grants administrator access to loopback requests without validating Origin headers. Attackers can craft malicious web pages that force victims to terminate the kernel process, read workspace configuration and proxy settings, and trigger administrative actions via zero-credential cross-origin requests from the victim's browser.
AI Analysis
Technical Summary
CVE-2026-100642 is a CSRF vulnerability in SiYuan note software affecting versions >=2.1.0 and <3.8.4. The vulnerability arises because the CheckAuth lock-screen pass-through branch improperly grants administrator access to loopback requests without validating the Origin header. This allows attackers to craft malicious web pages that trigger zero-credential cross-origin requests from a victim's browser, enabling administrative actions such as terminating kernel processes and reading workspace configuration and proxy settings.
Potential Impact
Successful exploitation allows an attacker to perform administrative actions on the victim's SiYuan instance without credentials. This includes terminating kernel processes and accessing sensitive workspace configuration and proxy settings, potentially leading to denial of service and information disclosure.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
CVE-2026-100642: Origin Validation Error in siyuan-note siyuan
Description
SiYuan versions from v2.1.0 before v3.8.4 contain a cross-site request forgery vulnerability in the CheckAuth lock-screen pass-through branch that grants administrator access to loopback requests without validating Origin headers. Attackers can craft malicious web pages that force victims to terminate the kernel process, read workspace configuration and proxy settings, and trigger administrative actions via zero-credential cross-origin requests from the victim's browser.
CVSS v4.0
Score 7.2high
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-2026-100642 is a CSRF vulnerability in SiYuan note software affecting versions >=2.1.0 and <3.8.4. The vulnerability arises because the CheckAuth lock-screen pass-through branch improperly grants administrator access to loopback requests without validating the Origin header. This allows attackers to craft malicious web pages that trigger zero-credential cross-origin requests from a victim's browser, enabling administrative actions such as terminating kernel processes and reading workspace configuration and proxy settings.
Potential Impact
Successful exploitation allows an attacker to perform administrative actions on the victim's SiYuan instance without credentials. This includes terminating kernel processes and accessing sensitive workspace configuration and proxy settings, potentially leading to denial of service and information disclosure.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
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: 6ab7c9a7f7a7c5410652fd2a
Added to database: 09/26/2026, 13:33:27 UTC
Last enriched: 09/26/2026, 14:03:48 UTC
Last updated: 09/27/2026, 01:57:11 UTC
Views: 10
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