CVE-2026-72811 — SiYuan versions <= v3.7.2 contain a SQL injection vulnerability in the backlink/mention…¶
Key facts
CVE-2026-72811 is a Critical (10.0) vulnerability: SiYuan versions <= v3.7.2 contain a SQL injection vulnerability in the backlink/mention…. This entry ships a detection-only PoC and a Docker test lab.
| CVE | CVE-2026-72811 |
| Severity | Critical (10.0) |
| Detection / prevention | — |
| PoC | poc.py |
| Source | 2026/CVE-2026-72811/ |
Details¶
English | 한국어
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.
Vulnerability Details¶
| Property | Value |
|---|---|
| CVE ID | CVE-2026-72811 |
| Type | SQLI |
| CVSS Score | 10.0 |
Proof of Concept¶
Download¶
# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2026/CVE-2026-72811/poc.py
Usage¶
# Run PoC against target
python3 poc.py --target <TARGET_URL>
# With authentication
python3 poc.py --target <TARGET_URL> --username <USER> --password <PASS>
⚠️ Warning: This PoC is for authorized security testing only. It uses detection-only techniques and does not exploit or damage target systems.
Test Lab¶
This repository includes a Docker-based test environment with both vulnerable and patched applications.
Quick Start¶
# Clone and navigate to CVE directory
cd CVE-2026-72811
# Start both applications
docker-compose up -d
# Run tests
./run-tests.sh # Linux/Mac
./run-tests.ps1 # Windows PowerShell
Application Endpoints¶
| Application | URL | Status |
|---|---|---|
| Vulnerable App | http://localhost:8080 | Shows vulnerability |
| Patched App | http://localhost:8081 | Demonstrates fix |
Directory Structure¶
├── README.md # English documentation
├── README_KO.md # Korean documentation
├── poc.py # PoC detection script
├── docker-compose.yml # Container orchestration
├── run-tests.sh # Linux/Mac test runner
├── run-tests.ps1 # Windows test runner
├── vulnerable-app/ # Vulnerable version
│ ├── app.py
│ ├── Dockerfile
│ └── requirements.txt
└── patched-app/ # Fixed version
├── app.py
├── Dockerfile
└── requirements.txt
References¶
- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-q2vg-7qgx-x5fc
- https://www.vulncheck.com/advisories/siyuan-before-sql-injection-via-backlink-search
Generated by PoC Generator on 2026-08-15T04:27:54.6225424
Frequently asked questions¶
What is CVE-2026-72811?¶
CVE-2026-72811 is a Critical (10.0) vulnerability: SiYuan versions <= v3.7.2 contain a SQL injection vulnerability in the backlink/mention…. This entry ships a detection-only PoC and a Docker test lab.
How do I detect CVE-2026-72811?¶
Run the detection-only PoC included with this entry against your Docker test lab to confirm whether a target is affected; pair it with your own IDS logging.
How do I block or mitigate CVE-2026-72811?¶
Upgrade to a fixed version per the vendor advisory; the NVD record lists the affected versions. Use the included PoC to verify your remediation.
For authorized security testing and research only. See the full source and NVD record.