CVE-2026-5015: elecV2P XSS Vulnerability in Logs Endpoint

CVE-2026-5015 Overview

A Cross-Site Scripting (XSS) vulnerability has been identified in elecV2 elecV2P versions up to 3.8.3. The vulnerability exists in an unknown function of the /logs endpoint component. Manipulation of the filename argument allows attackers to inject malicious scripts, enabling remote cross-site scripting attacks. The exploit has been publicly disclosed and the project maintainers were notified through an issue report but have not yet responded.

Critical Impact

This XSS vulnerability allows remote attackers to inject and execute arbitrary JavaScript code in the context of authenticated user sessions, potentially leading to session hijacking, credential theft, or unauthorized actions on behalf of legitimate users.

Affected Products

• elecV2 elecV2P up to version 3.8.3
• elecV2P /logs endpoint component
• Systems exposing elecV2P web interface to untrusted networks

Discovery Timeline

• 2026-03-28 - CVE-2026-5015 published to NVD
• 2026-03-30 - Last updated in NVD database

Technical Details for CVE-2026-5015

Vulnerability Analysis

This vulnerability is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation), commonly known as Cross-Site Scripting (XSS). The flaw resides in the /logs endpoint of the elecV2P application, where user-supplied input through the filename argument is not properly sanitized before being rendered in the web interface.

When a malicious filename parameter containing JavaScript code is processed by the vulnerable endpoint, the application fails to escape or encode special characters. This allows the injected script to execute within the browser context of any user viewing the affected page, potentially compromising user sessions and sensitive data.

The vulnerability can be exploited remotely without authentication, though user interaction is required for successful exploitation. The attack is network-accessible and has low complexity, making it relatively straightforward to exploit once discovered.

Root Cause

The root cause of this vulnerability stems from insufficient input validation and output encoding in the /logs endpoint handler. The application processes the filename argument without applying proper sanitization techniques such as HTML entity encoding or Content Security Policy enforcement. When log filenames or related parameters are displayed back to users, any embedded script content executes in the victim's browser.

Attack Vector

This vulnerability is exploited through crafted HTTP requests targeting the /logs endpoint. An attacker constructs a malicious URL containing JavaScript payload in the filename parameter and distributes it to potential victims through phishing emails, malicious websites, or other social engineering techniques.

When a victim clicks the malicious link while authenticated to elecV2P, the injected script executes with the victim's session privileges. This can enable attackers to steal session cookies, perform actions on behalf of the user, modify displayed content, or redirect users to malicious sites.

The vulnerability mechanism involves improper handling of the filename parameter in the /logs endpoint. When this parameter contains script tags or JavaScript event handlers, the application reflects them directly into the HTML response without adequate sanitization. For detailed technical information, refer to the GitHub Issue Discussion and VulDB entry #353900.

Detection Methods for CVE-2026-5015

Indicators of Compromise

• Unusual or malformed requests to the /logs endpoint containing script tags or JavaScript code in URL parameters
• HTTP access logs showing filename parameters with encoded characters like %3Cscript%3E or event handlers such as onerror=, onload=
• User reports of unexpected browser behavior or redirects when accessing elecV2P log functionality
• Evidence of session cookie theft attempts in network traffic logs

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block XSS patterns in requests to /logs endpoints
• Monitor HTTP access logs for suspicious patterns in the filename parameter including <script>, javascript:, and HTML event attributes
• Deploy client-side XSS detection mechanisms to identify script injection attempts
• Configure SentinelOne Singularity platform to monitor for anomalous web application behavior and potential XSS exploitation patterns

Monitoring Recommendations

• Enable detailed logging for all requests to elecV2P endpoints, particularly the /logs component
• Configure alerting on HTTP requests containing common XSS payload signatures
• Monitor for abnormal JavaScript execution or DOM modifications in browser-based detection tools
• Review Content Security Policy violation reports if CSP headers are implemented

How to Mitigate CVE-2026-5015

Immediate Actions Required

• Restrict access to elecV2P web interfaces to trusted networks only using firewall rules or reverse proxy authentication
• Implement a Web Application Firewall (WAF) with XSS protection rules in front of exposed elecV2P instances
• Enable Content Security Policy (CSP) headers to mitigate the impact of any successful XSS injection
• Audit user access logs for any suspicious activity targeting the /logs endpoint

Patch Information

As of the last update, the elecV2P project maintainers have not responded to the vulnerability disclosure. Monitor the elecV2P GitHub repository for security updates and patches. Organizations should consider implementing compensating controls until an official fix is available.

Workarounds

• Disable or restrict access to the /logs endpoint if not required for operations
• Implement input validation at the reverse proxy or load balancer level to reject requests with suspicious filename parameters
• Deploy network segmentation to isolate elecV2P instances from untrusted networks
• Consider implementing custom output encoding middleware if modifying the application is feasible

# Example: Nginx configuration to block suspicious XSS patterns
location /logs {
    # Block requests with common XSS patterns in query parameters
    if ($query_string ~* "(<script|javascript:|onerror=|onload=)") {
        return 403;
    }
    
    # Restrict access to trusted IP ranges
    allow 10.0.0.0/8;
    allow 192.168.0.0/16;
    deny all;
    
    proxy_pass http://elecv2p_backend;
}