CVE-2026-82650: SiYuan before v3.8.1 Path Traversal via /api/template/render

Severity: medium (CVSS 4.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-30 · updated 2026-08-31
Weakness: CWE-668

Description

SiYuan 3.8.0 contains a path traversal / sensitive file exposure vulnerability in the RenderTemplate function (kernel/model/template.go), reachable via the POST /api/template/render endpoint (kernel/api/template.go). The endpoint restricts the supplied path only to the workspace directory (util.IsAbsPathInWorkspace) but, unlike the file API's refuseToAccess() blocklist, applies no sensitive-path exclusion. This allows an authenticated attacker to read sensitive workspace files, including conf/conf.json, which contains the API token and cookie signing key. The issue is fixed in v3.8.1.

Affected products

siyuan-note siyuan: before 3.8.1 — fixed in 3.8.1

How to fix

Upgrade to a fixed version: siyuan-note siyuan 3.8.1. Check the vendor advisory for mitigations.

References

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