Siyuan Note up to 3.8.1 Full Text Search Block fullTextSearchBlock information disclosure

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.2$0-$5k0.00+

Summaryinfo

A vulnerability was found in Siyuan Note Siyuan up to 3.8.1. It has been classified as problematic. Affected by this vulnerability is an unknown functionality of the file /api/search/fullTextSearchBlock of the component Full Text Search Block. This manipulation causes information disclosure. This vulnerability is registered as CVE-2026-87810. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in Siyuan Note Siyuan up to 3.8.1 and classified as problematic. Affected by this vulnerability is an unknown code block of the file /api/search/fullTextSearchBlock of the component Full Text Search Block. The manipulation with an unknown input leads to a information disclosure vulnerability. The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality. The summary by CVE is:

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publish-mode readers can submit arbitrary search terms to learn whether matching content exists in hidden or unpublished documents and determine the number of matching blocks and pages.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-87810 since 09/09/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1592 for this issue.

Upgrading to version 3.8.2 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Siyuan 3.8.2

Timelineinfo

09/09/2026 Advisory disclosed
09/09/2026 +0 days CVE reserved
09/09/2026 +0 days VulDB entry created
09/09/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-87810 (🔒)
GCVE (CVE): GCVE-0-2026-87810
GCVE (VulDB): GCVE-100-401665

Entryinfo

Created: 09/09/2026 13:38
Changes: 09/09/2026 13:38 (77)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Interested in the pricing of exploits?

See the underground prices here!