CVE-2019-25700

Executive Summary

CVE-2019-25700 is an unauthenticated SQL injection vulnerability in the Kados R10 GreenBee application. The flaw exists in the sort_direction parameter, allowing remote attackers to inject arbitrary SQL statements. This can lead to unauthorized extraction of sensitive database information, modification of data, or potential escalation to full system compromise. No official patch has been released, and no public proof-of-concept (PoC) or exploit code is available at this time. The vulnerability is classified under MITRE ATT&CK tactic T1190 (Exploit Public-Facing Application) and is mapped to CWE-89 (SQL Injection).

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (No official vector assigned)
• Attack Vector: Network (likely)
• Attack Complexity: Low (likely)
• Privileges Required: None (likely)
• User Interaction: None (likely)
• Scope: Unchanged (likely)
• Confidentiality Impact: High (likely)
• Integrity Impact: High (likely)
• Availability Impact: Low (likely)

Threat Level: Critical – Unauthenticated SQL injection in a public-facing application with no patch available.

Deep Dive & Mechanics

The vulnerability resides in the sort_direction parameter, which is used to control the sorting order of query results. The application fails to sanitize or parameterize user input before incorporating it into SQL queries. An attacker can submit a malicious payload such as:

ASC; DROP TABLE users; --

This would cause the database to execute the injected SQL commands, potentially leading to data exfiltration, data manipulation, or denial of service.

The injection point is likely in a GET or POST request to a page that displays tabular data. The sort_direction parameter is expected to accept values like ASC or DESC, but no validation is performed.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

$sort_direction = $_GET['sort_direction'];
$query = "SELECT * FROM products ORDER BY price $sort_direction";
$result = mysqli_query($conn, $query);

Patched Code (Conceptual):

$allowed_directions = ['ASC', 'DESC'];
$sort_direction = $_GET['sort_direction'];
if (in_array($sort_direction, $allowed_directions)) {
    $query = "SELECT * FROM products ORDER BY price $sort_direction";
    $result = mysqli_query($conn, $query);
} else {
    // Handle error
}

The patched version uses a whitelist approach to restrict the sort_direction parameter to only allowed values, preventing SQL injection.

Exploitation & Lab Setup

Red Team

Lab Setup:

1. Deploy a vulnerable instance of Kados R10 GreenBee (e.g., using a Docker container or a local VM).
2. Identify the endpoint that uses the sort_direction parameter (e.g., /products?sort_direction=ASC).
3. Use a tool like sqlmap to automate exploitation:

sqlmap -u "http://target.com/products?sort_direction=ASC" --batch --dbs

Manual Exploitation:

• Inject a UNION-based payload to extract data:

ASC UNION SELECT 1,2,3,4,5,6,7,8,9,10--

• Use error-based or time-based techniques if UNION is blocked.

Blue Team

Detection:

• Monitor for unusual sort_direction parameter values (e.g., containing SQL keywords like UNION, SELECT, DROP).
• Look for repeated requests with varying sort_direction values from the same IP.
• Use a Web Application Firewall (WAF) to block SQL injection patterns.

Hunting:

• Search logs for sort_direction parameters containing ', --, ;, or UNION.
• Correlate with database error messages in application logs.

Indicators of Compromise (IOCs)

• Network:
  • HTTP requests with sort_direction containing SQL keywords (e.g., UNION, SELECT, DROP).
  • Unusual response sizes or database error messages in HTTP responses.
• Host:
  • Database logs showing unexpected queries or errors.
  • Application logs with SQL syntax errors.
• File:
  • No specific file-based IOCs.

Detection Engineering

YARA Rule

rule CVE_2019_25700_SQLi {
    meta:
        description = "Detects SQL injection attempts targeting CVE-2019-25700"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2019-25700"
    strings:
        $sqli1 = /sort_direction=.*(?:UNION|SELECT|DROP|INSERT|UPDATE|DELETE|--|;)/i
        $sqli2 = /sort_direction=.*(?:'|%27|"|%22)/i
    condition:
        any of them
}

Sigma Rule

title: CVE-2019-25700 SQL Injection Attempt
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects SQL injection attempts in sort_direction parameter
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        c-uri|contains: "sort_direction="
        c-uri|re: "sort_direction=.*(?:UNION|SELECT|DROP|INSERT|UPDATE|DELETE|--|;|'|%27)"
    condition: selection
falsepositives:
    - Legitimate use of SQL keywords in parameter values (unlikely)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2019-25700 SQL Injection Attempt"; flow:to_server; content:"sort_direction="; nocase; pcre:"/sort_direction=.*(?:UNION|SELECT|DROP|INSERT|UPDATE|DELETE|--|;|'|%27)/i"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the vulnerable endpoint if possible, or restrict access to it via firewall rules.
2. Implement input validation – whitelist allowed values for sort_direction (e.g., only ASC and DESC).
3. Use parameterized queries or prepared statements to prevent SQL injection.
4. Apply a Web Application Firewall (WAF) rule to block SQL injection patterns.

Long-Term Fix:

• The vendor (Kados) should release a security patch. Since no patch is available, consider migrating to a different product or implementing a custom fix.

Workaround:

• Modify the application code to use a whitelist approach as shown in the patched code example.

Valters IT

{/* [Security Hash: 1098F6816A7D676520797C8B] */}