CVE-2025-25222: Luxsoft Luxcal Web Calendar SQLi Flaw

CVE-2025-25222 Overview

CVE-2025-25222 is a critical SQL injection vulnerability affecting LuxCal Web Calendar, a popular web-based calendar application developed by Luxsoft. The vulnerability exists in the retrieve.php file and allows unauthenticated remote attackers to manipulate database queries, potentially leading to unauthorized access, modification, or deletion of sensitive calendar data.

The vulnerability impacts both the MySQL and SQLite versions of LuxCal Web Calendar prior to version 5.3.3M (MySQL) and 5.3.3L (SQLite). Organizations using this calendar software for scheduling and event management should prioritize patching immediately to prevent exploitation.

Critical Impact

Unauthenticated attackers can exploit this SQL injection to read, modify, or delete database contents without any user interaction required.

Affected Products

• LuxCal Web Calendar (MySQL version) prior to 5.3.3M
• LuxCal Web Calendar (SQLite version) prior to 5.3.3L
• luxsoft luxcal_web_calendar

Discovery Timeline

• 2025-02-18 - CVE-2025-25222 published to NVD
• 2025-09-15 - Last updated in NVD database

Technical Details for CVE-2025-25222

Vulnerability Analysis

This SQL injection vulnerability (CWE-89) in LuxCal Web Calendar allows attackers to inject malicious SQL statements through the retrieve.php endpoint. The attack vector is network-based and requires no authentication or user interaction, making it particularly dangerous for internet-facing installations.

When exploited, attackers can bypass application security controls entirely and interact directly with the underlying database. This enables extraction of sensitive calendar data, user credentials, and configuration information. Additionally, attackers can modify or delete existing records, potentially disrupting business operations that rely on the calendar system.

Root Cause

The root cause of this vulnerability is improper sanitization and validation of user-supplied input in the retrieve.php file. The application fails to properly parameterize SQL queries, allowing attacker-controlled input to be directly incorporated into database queries. This classic SQL injection pattern occurs when developers concatenate user input into SQL strings rather than using prepared statements or parameterized queries.

Attack Vector

The vulnerability is exploitable remotely over the network without any authentication requirements. An attacker can craft malicious HTTP requests to the retrieve.php endpoint containing SQL injection payloads. These payloads can be designed to:

• Extract database contents using UNION-based or blind SQL injection techniques
• Modify existing calendar entries, user accounts, or application settings
• Delete critical database records causing denial of service
• Potentially escalate to remote code execution depending on database permissions and server configuration

The attack requires no user interaction and can be automated, making mass exploitation feasible if vulnerable instances are exposed to the internet.

Detection Methods for CVE-2025-25222

Indicators of Compromise

• Unusual or malformed requests to retrieve.php containing SQL syntax characters such as single quotes, double dashes, or UNION keywords
• Database error messages in application logs indicating SQL syntax errors
• Unexpected database queries appearing in database server logs
• Anomalous data modifications or deletions in calendar-related database tables

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block SQL injection patterns targeting retrieve.php
• Monitor web server access logs for requests containing SQL injection payloads (e.g., ' OR 1=1, UNION SELECT, -- comments)
• Enable database query logging and alert on suspicious query patterns or error conditions
• Deploy SentinelOne Singularity to detect post-exploitation behaviors if attackers leverage SQL injection for further compromise

Monitoring Recommendations

• Configure real-time alerting for HTTP requests to retrieve.php with suspicious parameter values
• Monitor database server performance metrics for unusual query volumes or execution times
• Implement file integrity monitoring on LuxCal installation directories to detect unauthorized modifications
• Review authentication logs for signs of credential abuse following potential data exfiltration

How to Mitigate CVE-2025-25222

Immediate Actions Required

• Upgrade LuxCal Web Calendar to version 5.3.3M (MySQL) or 5.3.3L (SQLite) immediately
• If patching is not immediately possible, restrict access to retrieve.php at the web server level
• Implement WAF rules to filter SQL injection attempts targeting the vulnerable endpoint
• Review database audit logs for signs of previous exploitation attempts

Patch Information

Luxsoft has released patched versions addressing this vulnerability. Organizations should download and install the updated software from the official Luxsoft Download Page. Additional details and discussion about the vulnerability fix can be found in the Luxsoft Forum Discussion. The vulnerability was also documented in JVN Advisory JVN26024080.

Workarounds

• Block public access to retrieve.php using web server access controls or firewall rules until patching is completed
• Place the LuxCal Web Calendar behind a VPN or authentication proxy to limit exposure
• Implement database user privilege restrictions to minimize impact if exploitation occurs (e.g., read-only database user for the web application)
• Deploy a WAF with SQL injection detection rules as an interim protective measure

# Apache .htaccess example to restrict access to retrieve.php
<Files "retrieve.php">
    Require ip 192.168.1.0/24
    # Or completely deny access
    # Require all denied
</Files>