CVE-2026-101091: SiYuan before v3.8.4 SQL Injection via Block Query Embed

Vulnerability summary

CVE-2026-101091 is a high (CVSS 7.1) SQL Injection vulnerability in siyuan-note siyuan. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 16.1% of scored vulnerabilities.

Timeline

1. 28-09-2026
   PublishedVulnerability first disclosed.
2. 29-09-2026
   Last modifiedVulnerability information updated.

Description

SiYuan versions before v3.8.4 fail to properly validate SQL statements in block query embed blocks executed against siyuan.db. Attackers can craft malicious .sy documents with non-read-only SQL statements that execute automatically during background indexing, rendering, or export operations without authentication.

• CWE-89Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.