CVE-2026-59809 (GCVE-0-2026-59809)
Vulnerability from cvelistv5 – Published: 2026-08-22 12:26 – Updated: 2026-08-26 16:16
VLAI
EPSS
VEX
Title
SiYuan before v3.8.0 Secret Exfiltration via http_request URL
Summary
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.
Severity
4.9 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-26 15:55 UTC
CWE
- CWE-201 - Insertion of Sensitive Information Into Sent Data
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/siyuan-note/siyuan/security/ad… | vendor-advisory |
| https://www.vulncheck.com/advisories/siyuan-befor… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| siyuan-note | siyuan |
Affected:
0 , < 3.8.0
(semver)
Unaffected: 3.8.0 (semver) cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:* |
Date Public
2026-08-08 00:00
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