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CVE-2026-59809 Details

UNDERGOING ENRICHMENT

The CVE is currently being enriched by the Volerion team. The enrichment process results in the association of reference link tags, CVSS, and CPE applicability statement data.

Description

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.

Metrics

CVSS 3.x Severity and Vector Strings:

VolerionCVSS-B:…Vector:This vulnerability is currently being analyzed.

CNA: [email protected]CVSS-B:4.9 MEDIUMVector:CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.

URL	Source(s)	Tag(s)
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-853m-gvvm-6rvx	[email protected]
https://www.vulncheck.com/advisories/siyuan-before-secret-exfiltration-via-http-request-url	[email protected]

Weakness Enumeration

CWE-ID	CWE Name	Source
CWE-201	Insertion of Sensitive Information Into Sent Data	[email protected]

Affected Products

This vulnerability is currently being analyzed

Change History

3 change records found show changes

Date	Action	Recorded By
Aug 26, 2026	CVE Modified	[email protected]
Aug 26, 2026	CVE Modified	CISA-ADP
Aug 22, 2026	New CVE Received	[email protected]