CVE-2026-1476: Performance Evaluation (EDD) SQLi Vulnerability

CVE-2026-1476 Overview

An out-of-band SQL injection vulnerability (OOB SQLi) has been identified in the Performance Evaluation (EDD) application developed by Gabinete Técnico de Programación. This vulnerability exists in the Id_usuario parameter within the /evaluacion_acciones_ver_auto.aspx endpoint and allows attackers to extract sensitive information from the database through external channels without requiring the application to return data directly.

Critical Impact

This vulnerability enables unauthorized extraction of confidential database information through out-of-band channels, potentially compromising all stored data including user credentials, personal information, and business-critical records.

Affected Products

• Performance Evaluation (EDD) Application by Gabinete Técnico de Programación
• Quatuor Performance Evaluation System

Discovery Timeline

• 2026-01-27 - CVE-2026-1476 published to NVD
• 2026-01-29 - Last updated in NVD database

Technical Details for CVE-2026-1476

Vulnerability Analysis

This out-of-band SQL injection vulnerability differs from traditional SQL injection in that it does not rely on the application's HTTP response to exfiltrate data. Instead, attackers can leverage database-specific functions to establish communication channels with attacker-controlled infrastructure, enabling data extraction even when the application does not display query results. The vulnerability in the Id_usuario parameter allows for injection of malicious SQL statements that can trigger DNS lookups, HTTP requests, or other network communications containing sensitive data.

Out-of-band SQL injection is particularly dangerous because it bypasses traditional defensive measures that rely on monitoring application responses. The vulnerability affects the confidentiality and integrity of stored information, with attackers potentially able to read, modify, or delete database contents depending on database permissions.

Root Cause

The root cause is classified under CWE-89 (Improper Neutralization of Special Elements used in an SQL Command). The application fails to properly sanitize or parameterize user input in the Id_usuario parameter before incorporating it into SQL queries. This allows attackers to break out of the intended query structure and inject arbitrary SQL commands that the database server executes with the application's database privileges.

Attack Vector

The attack is network-accessible and requires no authentication or user interaction. An attacker can craft malicious HTTP requests targeting the /evaluacion_acciones_ver_auto.aspx endpoint with specially constructed values in the Id_usuario parameter. The injected SQL payload would typically leverage database-specific functions such as:

• Microsoft SQL Server: xp_dirtree, xp_fileexist, or xp_getfiledetails to trigger DNS lookups
• Oracle: UTL_HTTP, UTL_INADDR, or HTTPURITYPE to make outbound connections
• MySQL: LOAD_FILE() combined with network resources or DNS exfiltration techniques

The attacker receives the exfiltrated data on their controlled infrastructure through DNS queries, HTTP requests, or similar out-of-band mechanisms, making detection more challenging than traditional SQL injection attacks.

Detection Methods for CVE-2026-1476

Indicators of Compromise

• Unusual outbound DNS queries from the database server to unknown or suspicious domains
• Unexpected network connections from database servers to external IP addresses
• Anomalous database activity including queries with OOB-specific functions like xp_dirtree, UTL_HTTP, or similar
• Log entries showing malformed or suspicious values in the Id_usuario parameter

Detection Strategies

• Implement database activity monitoring (DAM) to detect suspicious SQL queries containing OOB function calls
• Deploy web application firewalls (WAF) with rules to detect SQL injection patterns in the Id_usuario parameter
• Monitor DNS logs for unusual query patterns originating from database servers
• Enable verbose logging on the /evaluacion_acciones_ver_auto.aspx endpoint to capture parameter values

Monitoring Recommendations

• Configure alerting for database server outbound network connections to non-whitelisted destinations
• Implement network segmentation to restrict database server internet access and enable anomaly detection
• Deploy SentinelOne Singularity XDR for endpoint detection and response on application and database servers
• Review web server access logs for requests to /evaluacion_acciones_ver_auto.aspx with encoded or unusual characters in query parameters

How to Mitigate CVE-2026-1476

Immediate Actions Required

• Restrict network access to the affected /evaluacion_acciones_ver_auto.aspx endpoint through firewall rules or access controls
• Implement input validation to whitelist acceptable values for the Id_usuario parameter
• Block database server outbound network access to prevent out-of-band data exfiltration
• Contact Gabinete Técnico de Programación for security patch availability information

Patch Information

Organizations should consult the INCIBE Security Notice for official remediation guidance and patch availability. Apply vendor-supplied patches immediately when available. In the interim, implement the workarounds described below to reduce exposure.

Workarounds

• Implement parameterized queries or prepared statements at the application code level if source code access is available
• Deploy a web application firewall (WAF) with SQL injection detection rules for the affected endpoint
• Restrict database user privileges to minimum required operations and disable dangerous stored procedures
• Isolate the affected application in a network segment with no outbound internet connectivity
• Implement strong input validation using allowlists for the Id_usuario parameter (numeric values only)

# Example: Restrict database server outbound connections (Linux iptables)
# Block all outbound connections from database server except to application server
iptables -A OUTPUT -m owner --uid-owner mysql -d <app_server_ip> -j ACCEPT
iptables -A OUTPUT -m owner --uid-owner mysql -j DROP