MEDIUM
SiYuan before v3.8.0 Secret Exfiltration via http_request URL
Published Aug 22, 2026
6.9
MEDIUMCVSS 4.0
EPSS 0.41%
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.
Affected products
-
Affected
- ≥ 0, < 3.8.0
Unaffected
- 3.8.0
Default status is the baseline for the product. Each version can override it (patched versions can be marked unaffected).
| Vendor | Product | Default status | Versions |
|---|---|---|---|
| Siyuan-Note | Siyuan | unaffected | Affected
Unaffected
|
No data.
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Weaknesses (1)
References (3)
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-64267 Advisory
- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-853m-gvvm-6rvx vendor-advisory
- https://www.vulncheck.com/advisories/siyuan-before-secret-exfiltration-via-http-request-url third-party-advisory
| Link | Providers | Tags |
|---|---|---|
| https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-64267 | Advisory | |
| https://github.com/siyuan-note/siyuan/security/advisories/GHSA-853m-gvvm-6rvx | vendor-advisory | |
| https://www.vulncheck.com/advisories/siyuan-before-secret-exfiltration-via-http-request-url | third-party-advisory |
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner VulnCheck
Published Aug 22, 2026
Updated Aug 26, 2026
Reserved Jul 7, 2026
Link CVE-2026-59809
CISA Vulnrichment
Updated Aug 26, 2026
Red Hat
No data
GitHub
No data