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

12 Oct 2026, 16:10

Type	Values Removed	Values Added
Summary		(es) SiYuan anterior a la v3.8.0 interpola marcadores de posición de secretos en el parámetro URL de destino de la herramienta MCP http_request, lo que permite a los atacantes exfiltrar secretos almacenados. Un cliente MCP puede elaborar una solicitud con una URL controlada por el atacante que contenga marcadores de posición de secretos para enviar valores de secretos en texto plano a cualquier host público sin confirmación.

Information

Published : 2026-08-22 13:16

Updated : 2026-10-12 16:10

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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