Vulnerability · Published Sep 26, 2026 · Assigned by VulnCheck

CVE-2026-100636SiYuan before v3.8.4 Path Traversal via exportBrowserHTML folder

High 7.6

In plain English

A high-severity path traversal in siyuan from siyuan-note. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 50% of all known vulnerabilities).

Severity (CVSS 3.1)7.6High

Exploit odds (30 days)0.6%top 50.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

SiYuan versions before v3.8.4 contain a path traversal vulnerability in the exportBrowserHTML endpoint that allows authenticated administrators to write arbitrary HTML content to index.html outside the workspace directory. Attackers can supply a folder parameter with directory traversal sequences to escape the export directory and overwrite index.html in any pre-existing kernel-writable location, enabling stored XSS or workspace defacement.

Affected products (as reported)

Vendor	Product	Versions
siyuan-note	siyuan	0 – before 3.8.4

Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L

References

GitHub Security Advisory (GHSA-jf98-m24w-gm9m) vendor-advisory
VulnCheck Advisory: SiYuan before v3.8.4 Path Traversal via exportBrowserHTML folder third-party-advisory