CVE-2026-59809

SiYuan before v3.8.0 interpolates secret placeholders into the destination URL parameter of the http_request MCP tool, allowing attackers to exfiltrate stored secrets. An MCP client can craft a request with an attacker-controlled URL containing secret placeholders to send plaintext secret values to any public host without confirmation.

CVSS v3 4.9 MEDIUM

4.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-853m-gvvm-6rvx
https://www.vulncheck.com/advisories/siyuan-before-secret-exfiltration-via-http-request-url

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-22 13:16

Updated : 2026-08-26 17:17

NVD link : CVE-2026-59809

Mitre link : CVE-2026-59809

CVE.ORG link : CVE-2026-59809

JSON object : View

Products Affected

No product.

CWE

CWE-201

Insertion of Sensitive Information Into Sent Data

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