Mend.io Vulnerability Database
The largest open source vulnerability database
What is a Vulnerability ID?
New vulnerability? Tell us about it!
CVE-2026-59809
Published:August 22, 2026
Updated:September 24, 2026
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.
Affected Packages
https://github.com/siyuan-note/siyuan.git (GITHUB):
Affected version(s) >=v0.1.0 <v3.8.0
Fix Suggestion:
Update to version v3.8.0
github.com/siyuan-note/siyuan (GO):
Affected version(s) >=v0.1.0 <v3.8.0
Fix Suggestion:
Update to version v3.8.0
Do you need more information?
Contact Us
CVSS v4
Base Score:
6.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
HIGH
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
4.9
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Insertion of Sensitive Information Into Sent Data
EPSS
Base Score:
0.24