Quantum Secular Labs / Blog / Advisories
CVE-2026-72811: SiYuan: SQL injection
CVE-2026-72811 is rated critical with a CVSS v3.1 base score of 10.0. Per its scoring, it can be exploited over the network, without authentication, without any user interaction.
Vulnerability description
SiYuan versions <= v3.7.2 contain a SQL injection vulnerability in the backlink/mention search query (kernel/model/backlink.go), which concatenates stored block metadata (title, name, alias, anchor text) and the client-supplied keyword into a SQL MATCH/search statement while escaping only the double-quote character and not the single quote. A single quote in the client keyword (first-order, reachable by an anonymous or RoleReader user on the publish surface) or in stored document metadata (second-order) breaks out of the string literal. Because the query runs on the main read-write siyuan.db handle via a statement-stacking-capable driver, an attacker can execute arbitrary SQL, enabling cross-notebook read and write. Fixed in v3.7.4.
Severity breakdown
CVSS v3.1 10.0: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: None. No account or prior access is needed.
- User interaction: None. No action from any user is needed.
- Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: None. No effect on availability.
Underlying weakness
CWE-89: Improper Neutralization of Special Elements used in an SQL Command
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.