Path Traversal in Siyuan-Note Siyuan
CVE-2026-77086
SiYuan before v3.7.4 fails to validate the packageName parameter in Bazaar install and uninstall endpoints, allowing authenticated administrators to perform path traversal via directory traversal sequences. Attackers with admin access can write arbitrary files to any location via install operations or recursively delete directories via uninstall operations by supplying crafted packageName values.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.010 (62.4th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 62nd percentile — 62.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.010 · change: +0.004
Affected products
Weakness classification (CWE)
References
- GitHub Security Advisory (GHSA-wr4w-7vjm-mmx3) (vendor-advisory)
- VulnCheck Advisory: SiYuan before v3.7.4 Path Traversal via packageName (third-party-advisory)
Frequently asked questions
- What is CVE-2026-77086?
- CVE-2026-77086 is a critical-severity vulnerability in Siyuan-Note Siyuan, classified under Path Traversal. CVSS score: 9.1/10. Published 2026-08-21.
- How severe is CVE-2026-77086?
- Critical severity. CVSS v3 base score is 9.1 out of 10.