CVE-2026-40259
SiYuan: Publish Reader Can Arbitrarily Delete Attribute View Files via removeUnusedAttributeView API
No known exploitation. EPSS puts it in the 43rd percentile. No fix published yet.
What to do
No fixed build or workaround is published yet. Limit exposure and watch for a patch.
What it is
From the CVE record
SiYuan is an open-source personal knowledge management system. In versions 3.6.3 and below, the /api/av/removeUnusedAttributeView endpoint is protected only by generic authentication that accepts publish-service RoleReader tokens. The handler passes a caller-controlled id directly to a model function that unconditionally deletes the corresponding attribute view file from the workspace without verifying that the caller has write privileges or that the target attribute view is actually unused. An authenticated publish-service reader can permanently delete arbitrary attribute view definitions by extracting publicly exposed data-av-id values from published content, causing breakage of database views and workspace rendering until manually restored. This issue has been fixed in version 3.6.4.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.5% chance of exploitation activity in the next 30 days, which ranks it in the 43rd percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
3 events over 4 days, from the signal feeds we watch.
- Record updated
- Publishedweakness classified
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Scored 8.1 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
Sources
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