CVE-2026-33476
HighPublic exploitSiyuan has an Unauthenticated Arbitrary File Read via Path Traversal
Published Mar 20, 2026 · Updated Aug 12, 2026 · Also known as GHSA-hhgj-gg9h-rjp7, GO-2026-4802
Key Facts
Patch immediately- CVE-2026-33476 is a high-severity vulnerability (CVSS 7.5 v3.1) affecting Siyuan (B3log), github.com/siyuan-note/siyuan/kernel (go).
- It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
- EPSS estimates a 3.1% probability of exploitation in the next 30 days.
- Fixed versions are available, including Siyuan 3.6.2.
- Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
CVSS v3.1
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS (30-day exploit likelihood)
3.1%
Higher than 87.4% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2026-33476 brief as a PDF
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Description
SiYuan is a personal knowledge management system. Prior to version 3.6.2, the Siyuan kernel exposes an unauthenticated file-serving endpoint under /appearance/*filepath. Due to improper path sanitization, attackers can perform directory traversal and read arbitrary files accessible to the server process. Authentication checks explicitly exclude this endpoint, allowing exploitation without valid credentials. Version 3.6.2 fixes this issue.
Affected Products
3 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| SiyuanB3log | >= < 3.6.2 | 3.6.2 |
| github.com/siyuan-note/siyuan/kernelgo | See advisory | n/a |
Patched Releases
Siyuan
3.6.2
Timeline
Publicly disclosed
Mar 20, 2026
Last updated
Aug 12, 2026
Weakness Type
- CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
- CWE-73 External Control of File Name or Path
References
- advisoryGHSA advisory
- advisoryhttps://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33476.json
- advisoryhttps://nvd.nist.gov/vuln/detail/CVE-2026-33476
- articlehttps://github.com/siyuan-note/siyuan/commit/009bb598b3beccc972aa5f1ed88b3b224326bf2a
- articlehttps://github.com/siyuan-note/siyuan/security/advisories/GHSA-hhgj-gg9h-rjp7
FAQ
Common Questions.
SiYuan is a personal knowledge management system.
Affected: Siyuan (B3log) versions >= < 3.6.2; github.com/siyuan-note/siyuan/kernel (go). The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Siyuan 3.6.2.
Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
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