CVE-2026-82234 (GCVE-0-2026-82234)

Vulnerability from cvelistv5 – Published: 2026-08-28 10:49 – Updated: 2026-08-28 16:10
VLAI
Title
SiYuan before v3.8.1 SSRF via DNS-Rebinding TOCTOU
Summary
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.
Severity
8.4 (High)
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
8.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 16:09 UTC
CWE
  • CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
References
Impacted products
Vendor Product Version CPE status
siyuan-note siyuan Affected: 0 , < 3.8.1 (semver)
Unaffected: 3.8.1 (semver)
    cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-13 00:00
Credits
joysinleung
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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