CVE-2026-87810: Exposure of Sensitive Information to an Unauthorized Actor in siyuan-note siyuan
Siyuan versions prior to 3.8.2 have an information disclosure vulnerability in the POST /api/search/fullTextSearchBlock endpoint. This endpoint filters private blocks from search results but still returns unfiltered match counts. As a result, unauthenticated users in publish mode can infer the existence and quantity of matching content in hidden or unpublished documents by submitting arbitrary search terms.
AI Analysis
Technical Summary
CVE-2026-87810 describes an information disclosure vulnerability in Siyuan note-taking software before version 3.8.2. The vulnerability exists in the fullTextSearchBlock API endpoint, which filters private blocks from search results but does not filter the count of matching blocks and pages. This allows unauthenticated users to learn whether certain content exists in hidden or unpublished documents and to determine the number of matching blocks and pages, potentially exposing sensitive information.
Potential Impact
An unauthenticated attacker can infer the presence and quantity of sensitive or private content in hidden or unpublished documents by submitting search queries. Although the actual private content is not directly exposed, the leakage of match counts can reveal information about the existence and volume of sensitive data, constituting an information disclosure risk.
Mitigation Recommendations
A fix is available in Siyuan version 3.8.2 that addresses this vulnerability. Users should upgrade to version 3.8.2 or later to remediate this issue. Patch status is not explicitly confirmed in the vendor advisory, but the affected versions are clearly stated as prior to 3.8.2, indicating that upgrading to 3.8.2 or later resolves the vulnerability.
CVE-2026-87810: Exposure of Sensitive Information to an Unauthorized Actor in siyuan-note siyuan
Description
Siyuan versions prior to 3.8.2 have an information disclosure vulnerability in the POST /api/search/fullTextSearchBlock endpoint. This endpoint filters private blocks from search results but still returns unfiltered match counts. As a result, unauthenticated users in publish mode can infer the existence and quantity of matching content in hidden or unpublished documents by submitting arbitrary search terms.
CVSS v4.0
Score 6.9medium
Affected software
pkg:github/siyuan-note/siyuanRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-87810 describes an information disclosure vulnerability in Siyuan note-taking software before version 3.8.2. The vulnerability exists in the fullTextSearchBlock API endpoint, which filters private blocks from search results but does not filter the count of matching blocks and pages. This allows unauthenticated users to learn whether certain content exists in hidden or unpublished documents and to determine the number of matching blocks and pages, potentially exposing sensitive information.
Potential Impact
An unauthenticated attacker can infer the presence and quantity of sensitive or private content in hidden or unpublished documents by submitting search queries. Although the actual private content is not directly exposed, the leakage of match counts can reveal information about the existence and volume of sensitive data, constituting an information disclosure risk.
Mitigation Recommendations
A fix is available in Siyuan version 3.8.2 that addresses this vulnerability. Users should upgrade to version 3.8.2 or later to remediate this issue. Patch status is not explicitly confirmed in the vendor advisory, but the affected versions are clearly stated as prior to 3.8.2, indicating that upgrading to 3.8.2 or later resolves the vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-09T10:30:15.669Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6aa14507acd9273b49403554
Added to database: 09/09/2026, 11:37:43 UTC
Last enriched: 09/09/2026, 11:52:49 UTC
Last updated: 09/09/2026, 11:55:44 UTC
Views: 3
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