CVE-2026-23851Public exploitNetwork attack vector

Admin-level arbitrary file read via unchecked source paths

Published Jan 19, 2026 · Updated Jan 19, 2026

Path traversal in SiYuan before 3.5.4 allows remote authenticated users to read arbitrary server files through a file-copy API. The globalCopyFiles handler in kernel/api/file.go accepts srcs from JSON and copies each existing path into the workspace without restricting it to an authorized directory. The endpoint requires an authenticated, non-read-only administrator; copied files become retrievable workspace assets, exposing their contents.

CVSS severity8.3
High
EPSS probability0.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Path traversal in SiYuan before 3.5.4 allows remote authenticated users to read arbitrary server files through a file-copy API. The globalCopyFiles handler in kernel/api/file.go accepts srcs from JSON and copies each existing path into the workspace without restricting it to an authorized directory. The endpoint requires an authenticated, non-read-only administrator; copied files become retrievable workspace assets, exposing their contents.

The record

CVE
CVE-2026-23851
Published
Jan 19, 2026
Updated
Jan 19, 2026
Vendor
SiYuan Note
Product
SiYuan
Classifications
CWE-22, T1005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 3.5.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

SiYuan Note · SiYuanversion=< 3.5.4

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
8.3GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1005Data from Local System

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo