CVE-2026-28408: Wegia Auth Bypass Vulnerability

CVE-2026-28408 Overview

CVE-2026-28408 is a critical authentication bypass vulnerability in WeGIA, an open-source web manager application designed for charitable institutions. The vulnerability exists in the adicionar_tipo_docs_atendido.php script, which fails to implement proper authentication and authorization controls. This script bypasses the application's central controller, allowing unauthenticated remote attackers to access functionality intended exclusively for authenticated employees and inject unauthorized data into the application server's storage.

Critical Impact

Unauthenticated attackers can remotely access employee-restricted features and inject massive amounts of unauthorized data into the application's storage, potentially compromising the integrity of charitable institution operations.

Affected Products

• WeGIA versions prior to 3.6.5
• WeGIA web manager installations with exposed adicionar_tipo_docs_atendido.php endpoint
• Charitable institution systems running vulnerable WeGIA deployments

Discovery Timeline

• 2026-02-27 - CVE-2026-28408 published to NVD
• 2026-03-03 - Last updated in NVD database

Technical Details for CVE-2026-28408

Vulnerability Analysis

This vulnerability stems from an authentication bypass weakness (CWE-287) in WeGIA's document type management functionality. The affected script, adicionar_tipo_docs_atendido.php, operates outside the application's standard security architecture by not routing through the central controller that typically enforces authentication and authorization checks.

When a request is made directly to this endpoint, the application fails to verify whether the requester is an authenticated user with appropriate permissions. This allows external parties to interact with features that should be restricted to authorized employees only. The lack of access controls enables attackers to inject data directly into the server's storage systems without any validation of their identity or authorization level.

Root Cause

The root cause of CVE-2026-28408 is improper access control implementation. The adicionar_tipo_docs_atendido.php script was developed outside the application's centralized authentication framework, lacking both session validation and permission verification mechanisms. This architectural oversight means the script accepts and processes requests from any source, treating all incoming requests as legitimate regardless of authentication status.

Attack Vector

Exploitation of this vulnerability requires network access to the WeGIA application. An attacker can craft HTTP requests using standard tools such as Postman, curl, or a web browser to directly access the vulnerable endpoint. By navigating to or sending requests to adicionar_tipo_docs_atendido.php, attackers bypass all authentication requirements and gain access to document type management features.

The attack does not require any privileges, user interaction, or specialized exploitation techniques. Once the endpoint is identified, an attacker can automate requests to inject large volumes of unauthorized data into the application's storage, potentially disrupting operations, corrupting records, or using the system for malicious data storage purposes. For detailed technical information, see the GitHub Security Advisory.

Detection Methods for CVE-2026-28408

Indicators of Compromise

• Unexpected HTTP requests to adicionar_tipo_docs_atendido.php from external IP addresses or unauthenticated sessions
• Rapid increase in document type records without corresponding legitimate administrative activity
• Anomalous data entries in the application database that do not match typical organizational patterns
• Web server logs showing direct access attempts to adicionar_tipo_docs_atendido.php bypassing normal application navigation flows

Detection Strategies

• Implement web application firewall (WAF) rules to monitor and alert on direct access attempts to adicionar_tipo_docs_atendido.php
• Configure log monitoring to detect requests to the vulnerable endpoint without valid session tokens
• Deploy integrity monitoring on database tables related to document types to identify unauthorized insertions
• Use endpoint detection solutions to identify automated request patterns indicative of exploitation attempts

Monitoring Recommendations

• Enable detailed access logging for all PHP scripts in the WeGIA installation directory
• Establish baseline metrics for normal document type creation rates and alert on deviations
• Monitor for requests originating from API testing tools (Postman, curl) in User-Agent headers targeting administrative endpoints
• Implement real-time alerting for any access to administrative functions without prior successful authentication events

How to Mitigate CVE-2026-28408

Immediate Actions Required

• Upgrade WeGIA to version 3.6.5 or later immediately to address this vulnerability
• If immediate patching is not possible, restrict network access to the adicionar_tipo_docs_atendido.php endpoint
• Review application logs for evidence of prior exploitation and assess data integrity
• Audit all document type records for unauthorized entries that may have been injected through exploitation

Patch Information

The WeGIA development team has released version 3.6.5 which addresses this authentication bypass vulnerability. The patch integrates proper authentication and authorization checks into the adicionar_tipo_docs_atendido.php script, ensuring it routes through the application's central controller security mechanisms. Organizations should update to version 3.6.5 or later by following the GitHub Security Advisory instructions.

Workarounds

• Implement web server access controls to deny external requests to adicionar_tipo_docs_atendido.php until patching is complete
• Deploy a reverse proxy or WAF rule requiring authentication headers for all requests to the vulnerable endpoint
• Temporarily rename or relocate the vulnerable script to prevent direct URL access while maintaining application functionality through approved channels
• Implement IP-based allowlisting to restrict access to administrative endpoints to trusted internal networks only

# Apache .htaccess workaround to restrict access to vulnerable endpoint
<Files "adicionar_tipo_docs_atendido.php">
    # Deny all external access
    Require all denied
    # Allow only from trusted internal network
    Require ip 10.0.0.0/8 192.168.0.0/16
</Files>