CVE-2025-40639: Sbitsoft Eventobot SQLi Vulnerability

CVE-2025-40639 Overview

A SQL injection vulnerability has been identified in Sbitsoft Eventobot, a web-based event management application. This vulnerability allows an attacker to retrieve, create, update, and delete database contents through the promo_send parameter in the /assets/php/calculate_discount.php endpoint. The flaw enables malicious actors to manipulate SQL queries executed by the backend database, potentially leading to complete database compromise.

Critical Impact

Attackers can exploit this SQL injection flaw to extract sensitive data, modify or delete database records, and potentially escalate access to underlying server systems through database-level attack techniques.

Affected Products

• Sbitsoft Eventobot (all versions)

Discovery Timeline

• 2026-03-09 - CVE-2025-40639 published to NVD
• 2026-03-10 - Last updated in NVD database

Technical Details for CVE-2025-40639

Vulnerability Analysis

This SQL injection vulnerability (CWE-89) affects the discount calculation functionality within Sbitsoft Eventobot. The vulnerable endpoint /assets/php/calculate_discount.php fails to properly sanitize the promo_send parameter before incorporating it into SQL queries. This lack of input validation allows attackers to inject arbitrary SQL commands that are executed against the backend database with the privileges of the application's database user.

The attack surface is network-accessible and requires low-privilege authentication to exploit. Successful exploitation provides attackers with the ability to perform complete CRUD (Create, Read, Update, Delete) operations on the database, compromising data confidentiality, integrity, and potentially availability.

Root Cause

The root cause is improper input validation and lack of parameterized queries in the calculate_discount.php script. The promo_send parameter is directly concatenated into SQL queries without proper sanitization or the use of prepared statements. This allows user-controlled input to modify the intended SQL query structure, enabling attackers to inject malicious SQL code.

Attack Vector

The vulnerability is exploitable over the network by authenticated users with low privileges. An attacker can craft malicious HTTP requests to the /assets/php/calculate_discount.php endpoint, inserting SQL injection payloads into the promo_send parameter. The injected code is then executed by the database server, allowing the attacker to:

1. Extract sensitive information from database tables (user credentials, personal data, financial records)
2. Modify existing records or insert new malicious data
3. Delete critical database content
4. Potentially execute stored procedures or access additional database functionality

The attack requires no user interaction and can be automated for mass exploitation. Attackers typically use techniques such as UNION-based injection, blind SQL injection, or time-based blind injection depending on the application's response behavior.

Detection Methods for CVE-2025-40639

Indicators of Compromise

• Unusual HTTP requests to /assets/php/calculate_discount.php with suspicious characters in the promo_send parameter (e.g., single quotes, UNION statements, OR 1=1 patterns)
• Database logs showing unexpected queries or access to tables not typically accessed by the discount calculation function
• Web server logs containing URL-encoded SQL keywords such as %27, UNION, SELECT, DROP, or --
• Abnormal database activity including bulk data exports or unauthorized modifications

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block common SQL injection patterns targeting the vulnerable parameter
• Implement database activity monitoring to alert on suspicious query patterns or unauthorized data access
• Configure intrusion detection systems (IDS) with signatures for SQL injection attack payloads
• Enable detailed logging on the web server and database to capture forensic evidence of exploitation attempts

Monitoring Recommendations

• Monitor HTTP request logs for anomalous patterns in requests to /assets/php/calculate_discount.php
• Set up alerts for database errors that may indicate failed injection attempts
• Track database query execution times that deviate significantly from normal baselines, which may indicate time-based blind SQL injection
• Review database user privilege usage for unexpected elevation or access to sensitive tables

How to Mitigate CVE-2025-40639

Immediate Actions Required

• Restrict access to the /assets/php/calculate_discount.php endpoint using IP whitelisting or additional authentication controls until a patch is available
• Deploy WAF rules specifically targeting SQL injection attempts in the promo_send parameter
• Review database permissions to ensure the application uses a least-privilege database account
• Audit database logs for signs of prior exploitation and assess data integrity

Patch Information

No official patch information is currently available from Sbitsoft. Organizations should monitor the INCIBE Security Notice for updates on remediation guidance and contact Sbitsoft directly for patch availability.

Workarounds

• Implement input validation at the application layer to reject requests containing SQL metacharacters in the promo_send parameter
• Use a reverse proxy or WAF to filter malicious requests before they reach the vulnerable application
• Consider disabling the discount calculation functionality temporarily if it is not business-critical
• Segment the database server network to limit lateral movement in case of successful exploitation

# Example WAF rule to block SQL injection in promo_send parameter
# ModSecurity Rule Example
SecRule ARGS:promo_send "@detectSQLi" \
    "id:1001,\
    phase:2,\
    deny,\
    status:403,\
    msg:'SQL Injection attempt detected in promo_send parameter',\
    log,\
    severity:CRITICAL"