---
id: CVE-2026-87810
title: Siyuan before v3.8.2 Information Disclosure via fullTextSearchBlock
summary: >-
  Siyuan before v3.8.2 contains an information disclosure vulnerability in the
  POST /api/search/fullTextSearchBlock endpoint that filters private blocks from
  results but returns unfiltered match counts. Unauthenticated publish-mode
  readers…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'
cvssSource: cna
cwe:
  - CWE-200
vendor: siyuan-note
product: siyuan
affected:
  - siyuan < 3.8.2
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-14T13:06:21.485020Z'
exploitAvailable: true
published: '2026-09-09'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T13:06:42.069Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-87810'
references:
  - url: >-
      https://github.com/siyuan-note/siyuan/security/advisories/GHSA-g45v-hxvm-wccj
    label: GitHub Security Advisory (GHSA-g45v-hxvm-wccj)
  - url: >-
      https://www.vulncheck.com/advisories/siyuan-before-3.8.2-information-disclosure-via-fulltextsearchblock
    label: >-
      VulnCheck Advisory: Siyuan before v3.8.2 Information Disclosure via
      fullTextSearchBlock
tags:
  - cve.org
  - exploit-available
epss: 0.00343
epssPercentile: 0.25106
ingestedAt: '2026-09-14T15:23:07.426Z'
---

## Overview

Siyuan before v3.8.2 contains an information disclosure vulnerability in the POST /api/search/fullTextSearchBlock endpoint that filters private blocks from results but returns unfiltered match counts. Unauthenticated publish-mode readers can submit arbitrary search terms to learn whether matching content exists in hidden or unpublished documents and determine the number of matching blocks and pages.

## Affected

- `siyuan < 3.8.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.