CVE-2019-25696: Marmotech Kados SQL Injection Vulnerability

CVE-2019-25696 Overview

Kados R10 GreenBee contains an SQL injection vulnerability that allows attackers to manipulate database queries by injecting SQL code through the language_tag parameter. Attackers can submit malicious SQL statements in the language_tag parameter to extract sensitive database information or modify data. This vulnerability falls under CWE-89 (Improper Neutralization of Special Elements used in an SQL Command).

Critical Impact

Successful exploitation allows unauthenticated remote attackers to extract sensitive database information, modify data, or potentially escalate to further system compromise through SQL injection attacks.

Affected Products

• Marmotech Kados R10 GreenBee

Discovery Timeline

• 2026-04-05 - CVE CVE-2019-25696 published to NVD
• 2026-04-07 - Last updated in NVD database

Technical Details for CVE-2019-25696

Vulnerability Analysis

This SQL injection vulnerability exists in the Marmotech Kados R10 GreenBee application due to insufficient input validation of the language_tag parameter. When user-supplied input is passed to the language_tag parameter, the application fails to properly sanitize or parameterize the input before incorporating it into SQL queries. This allows an attacker to break out of the intended query structure and inject arbitrary SQL commands.

The vulnerability is accessible over the network without authentication, meaning any remote attacker can exploit it without requiring credentials or user interaction. The impact primarily affects data confidentiality with high severity, as attackers can extract sensitive information from the database. There is also a low integrity impact, indicating potential for data modification.

Root Cause

The root cause of this vulnerability is improper input validation and the use of unsanitized user input in SQL query construction. The language_tag parameter accepts user input that is directly concatenated into SQL statements without proper escaping, parameterized queries, or prepared statements. This fundamental coding flaw allows SQL metacharacters to alter the logical structure of the intended query.

Attack Vector

The attack is conducted over the network (AV:N) with low attack complexity (AC:L). No privileges are required (PR:N) and no user interaction is needed (UI:N), making this vulnerability particularly dangerous. An attacker can craft malicious HTTP requests containing SQL injection payloads in the language_tag parameter. These payloads can include UNION-based injections to extract data from other tables, boolean-based blind SQL injection techniques, or time-based blind SQL injection for data exfiltration when direct output is not available.

The vulnerability can be exploited through techniques such as:

• UNION SELECT statements to retrieve data from arbitrary database tables
• Stacked queries to execute multiple SQL commands (if supported by the database)
• Subqueries to extract database metadata and enumerate table structures
• Conditional statements for blind SQL injection data extraction

For detailed technical analysis and proof-of-concept information, refer to Exploit-DB #46505 and the VulnCheck Advisory.

Detection Methods for CVE-2019-25696

Indicators of Compromise

• Unusual database queries or errors in application logs containing SQL syntax errors or unexpected UNION/SELECT statements
• HTTP requests with suspicious characters in the language_tag parameter such as single quotes, double dashes, OR statements, or UNION SELECT keywords
• Abnormal database access patterns or queries accessing sensitive tables not typically used by the application
• Increased database load or response times indicating blind SQL injection enumeration attempts

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block SQL injection patterns in the language_tag parameter
• Implement database activity monitoring to alert on unusual query patterns, especially those containing UNION, SELECT, or information_schema references
• Enable detailed application logging to capture all requests to endpoints handling the language_tag parameter
• Use intrusion detection signatures targeting common SQL injection payloads and encoding variations

Monitoring Recommendations

• Monitor HTTP access logs for requests containing SQL keywords (SELECT, UNION, INSERT, UPDATE, DELETE) in parameter values
• Set up alerting for database errors that may indicate injection attempts such as syntax errors or type conversion failures
• Implement rate limiting on endpoints that process the language_tag parameter to slow down automated exploitation attempts
• Review database audit logs for queries accessing sensitive tables or system metadata tables

How to Mitigate CVE-2019-25696

Immediate Actions Required

• Identify all instances of Marmotech Kados R10 GreenBee in your environment and assess exposure
• Implement WAF rules to filter SQL injection attempts targeting the language_tag parameter
• Consider disabling or restricting access to the affected functionality until a patch is available
• Apply network segmentation to limit database access from compromised application servers

Patch Information

Review the SourceForge Project Kados and Kados Official Website for any available security updates or patches. Consult the VulnCheck Advisory for the latest remediation guidance.

Workarounds

• Implement input validation on the language_tag parameter to allow only expected values (whitelist approach)
• Use parameterized queries or prepared statements if modifying the source code is possible
• Deploy a Web Application Firewall with SQL injection detection rules in front of the application
• Apply the principle of least privilege to database accounts used by the application to limit the impact of successful exploitation

# Example WAF rule for ModSecurity to block SQL injection in language_tag parameter
SecRule ARGS:language_tag "@detectSQLi" \
    "id:100001,\
    phase:2,\
    block,\
    msg:'SQL Injection attempt detected in language_tag parameter',\
    log,\
    severity:CRITICAL"