4.4
MediumCVSS 3.1 · from VulnCheck
CVE-2026-116171
SiYuan 3.5.4 before 3.8.7 Sensitive Path Bypass via Windows Extended-Length Prefix
siyuan · Path traversal · CWE-22Affectedsiyuan
FixUpdate to 3.8.7 or newer
PublishedOct 25, 13:20 · VulnCheck
ScoredOct 25 · 4.4 · VulnCheck
Exploit code publicNone known · checked 21:18 UTC
ExploitedNone known · CISA KEV checked 22:04 UTC
What we know
No known exploitation. CISA KEV, checked 22:04 UTC.
No public exploit code known. Exploit-DB, Metasploit, Nuclei, checked 21:18 UTC.
An attacker needs network access and an account. CVSS: network, high privileges.
It only works under certain conditions, which makes it harder to pull off. CVSS: high attack complexity.
A successful attack can read data. CVSS impact.
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.
From VulnCheck
Affected and fixed versions
ProductAffectedFixed insiyuan3.5.4 – before 3.8.73.8.7siyuanNot affected3.8.7
Exploit code
Exploit-DBnone knownMetasploitnone knownNucleinone known