CVE-2026-82234

high

Description

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.

References

https://www.vulncheck.com/advisories/siyuan-before-3.8.1-ssrf-via-dns-rebinding-toctou

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-x8gv-g2g3-65fj

Details

Source: Mitre, NVD

Published: 2026-08-28

Updated: 2026-08-28

Risk Information

CVSS v2

Base Score: 8.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:P/A:N

Severity: High

CVSS v3

Base Score: 8.2

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

Severity: High

CVSS v4

Base Score: 8.4

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N

Severity: High

EPSS

EPSS: 0.00321