Vulnerability · Published Oct 25, 2026 · Assigned by VulnCheck

CVE-2026-116171SiYuan 3.5.4 before 3.8.7 Sensitive Path Bypass via Windows Extended-Length Prefix

Medium 4.4

In plain English

A medium-severity path traversal in siyuan from siyuan-note. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities).

Severity (CVSS 3.1)4.4Medium

Exploit odds (30 days)0.5%top 58.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

SiYuan 3.5.4 before 3.8.7 on Windows contains a sensitive-path denylist bypass in IsSensitivePath because the Windows extended-length prefix (\\?\) survives filepath.Clean and matches no forbidden prefix. Authenticated API callers can prepend the prefix to localPath in /api/import/importStdMd to copy workspace conf files, including the API token and TLS private keys, into assets served to unauthenticated clients.

Affected products (as reported)

Vendor	Product	Versions
siyuan-note	siyuan	3.5.4 – before 3.8.7

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

References

GitHub Security Advisory (GHSA-6gmc-424x-xgpm) vendor-advisory
VulnCheck Advisory: SiYuan 3.5.4 before 3.8.7 Sensitive Path Bypass via Windows Extended-Length Prefix third-party-advisory