HOMEVULNERABILITIESCVE-2026-40318
HIGH

CVE-2026-40318

CWE-24Published: April 16, 2026· Updated: Apr 20, 2026

8.5
CVSS v3.1
EPSS:0.06%probability of exploitation in 30 daysPercentile:18.4th

Official Description

SiYuan is an open-source personal knowledge management system. In versions 3.6.3 and prior, the /api/av/removeUnusedAttributeView endpoint constructs a filesystem path using the user-controlled id parameter without validation or path boundary enforcement. An attacker can inject path traversal sequences such as ../ into the id value to escape the intended directory and delete arbitrary .json files on the server, including global configuration files and workspace metadata. This issue has been fixed in version 3.6.4.

NVD Source

Technical Analysis

CVE-2026-40318 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 8.5.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeChanged
Impact
ConfidentialityNone
IntegrityLow
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H

Affected Vendors & Products

b3log1 product
siyuan
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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Official Patches & Advisories

All References (2)

Quick Facts

CVE IDCVE-2026-40318
CVSS Score8.5 / 10
SeverityHIGH
WeaknessCWE-24
CISA KEVNo
EPSS (30d)0.06%
Affected1 vendor
PublishedApr 16, 2026

Related CVEs (CWE-24)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2026-40318 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.