CVE-2026-82234

SiYuan versions before v3.8.1 contain a server-side request forgery vulnerability in the http_request and web_fetch agent tools that perform DNS resolution only at guard time without validating the connect-time resolution. Attackers can use DNS rebinding to answer the guard resolution with a public IP and the connect resolution with a private or metadata IP, bypassing the SSRF defense to access cloud instance metadata and internal services.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-x8gv-g2g3-65fj
https://www.vulncheck.com/advisories/siyuan-before-3.8.1-ssrf-via-dns-rebinding-toctou

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 12:16

Updated : 2026-08-28 20:20

NVD link : CVE-2026-82234

Mitre link : CVE-2026-82234

CVE.ORG link : CVE-2026-82234

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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