siyuan-note SiYuan up to 3.7.x Http Request MCP Tool missing encryption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.5$0-$5k2.59

Summaryinfo

A vulnerability marked as problematic has been reported in siyuan-note SiYuan up to 3.7.x. This issue affects some unknown processing of the component Http Request MCP Tool. This manipulation causes missing encryption. This vulnerability is handled as CVE-2026-59809. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability has been found in siyuan-note SiYuan up to 3.7.x and classified as problematic. Affected by this vulnerability is an unknown code of the component Http Request MCP Tool. The manipulation with an unknown input leads to a missing encryption vulnerability. The CWE definition for the vulnerability is CWE-311. The product does not encrypt sensitive or critical information before storage or transmission. As an impact it is known to affect confidentiality. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-59809 since 07/07/2026. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation needs additional levels of successful authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1600 for this issue.

Upgrading to version 3.8.0 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 3.6
VulDB Meta Temp Score: 3.5

VulDB Base Score: 2.2
VulDB Temp Score: 2.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.9
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Missing encryption
CWE: CWE-311 / CWE-310
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: SiYuan 3.8.0

Timelineinfo

07/07/2026 CVE reserved
08/22/2026 +46 days Advisory disclosed
08/22/2026 +0 days VulDB entry created
08/22/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-59809 (🔒)
GCVE (CVE): GCVE-0-2026-59809
GCVE (VulDB): GCVE-100-394321

Entryinfo

Created: 08/22/2026 15:04
Changes: 08/22/2026 15:04 (76)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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