CVE-2026-5016: elecV2P SSRF Vulnerability

CVE-2026-5016 Overview

A Server-Side Request Forgery (SSRF) vulnerability was identified in elecV2 elecV2P up to version 3.8.3. This vulnerability affects the eAxios function within the /mock file of the URL Handler component. Manipulation of the req argument enables attackers to forge server-side requests, potentially allowing unauthorized access to internal services and data exfiltration. The vulnerability can be exploited remotely without authentication, and a public exploit is available.

Critical Impact
Remote attackers can exploit this SSRF vulnerability to access internal network resources, potentially leading to information disclosure, internal service enumeration, and further exploitation of backend systems.

Affected Products

elecV2 elecV2P versions up to and including 3.8.3

Discovery Timeline

2026-03-28 - CVE-2026-5016 published to NVD
2026-03-30 - Last updated in NVD database

Technical Details for CVE-2026-5016

Vulnerability Analysis

This Server-Side Request Forgery (SSRF) vulnerability exists in the URL Handler component of elecV2P, specifically within the eAxios function located in the /mock endpoint. The vulnerability stems from inadequate validation and sanitization of user-controlled input in the req argument, which allows attackers to manipulate the server into making arbitrary HTTP requests to unintended destinations.

SSRF vulnerabilities are particularly dangerous because they allow attackers to bypass network access controls and interact with internal services that would normally be inaccessible from the external network. In the context of elecV2P, successful exploitation could enable attackers to probe internal network infrastructure, access cloud metadata services, or interact with other backend services running on the same server or internal network.

The vulnerability is classified under CWE-918 (Server-Side Request Forgery), which describes scenarios where a web application fetches remote resources based on user-supplied URLs without proper validation. The project maintainers were notified through GitHub Issue #202 but have not responded as of the last update.

Root Cause

The root cause of this vulnerability lies in the insufficient input validation within the eAxios function when processing user-supplied URL parameters. The function accepts the req argument without adequately verifying that the requested URL points to a legitimate external resource. This allows attackers to inject URLs targeting internal resources, localhost services, or cloud provider metadata endpoints that should not be accessible from external requests.

Attack Vector

The attack vector for CVE-2026-5016 is network-based, requiring no authentication or user interaction. An attacker can craft malicious HTTP requests to the /mock endpoint with a manipulated req parameter containing URLs targeting internal services or sensitive endpoints.

The exploitation process involves sending a request to the vulnerable /mock endpoint with a crafted URL in the req parameter. The server then processes this request using the eAxios function, which fetches the attacker-specified URL. This enables the attacker to access internal services such as metadata endpoints (e.g., http://169.254.169.254/ on cloud platforms), internal APIs, or localhost services. For detailed technical information about the vulnerability, refer to the VulDB entry #353901 and the associated GitHub issue.

Detection Methods for CVE-2026-5016

Indicators of Compromise

Unusual outbound requests from the elecV2P server to internal IP ranges (e.g., 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16)
HTTP requests to cloud metadata endpoints such as 169.254.169.254 or cloud-specific metadata URLs
Access logs showing requests to the /mock endpoint with suspicious URL parameters referencing internal hostnames or localhost
Unexpected network traffic patterns from the server to previously uncontacted internal services

Detection Strategies

Implement Web Application Firewall (WAF) rules to detect and block requests containing internal IP addresses or localhost references in URL parameters
Monitor application logs for requests to the /mock endpoint with non-standard URL schemes or internal network addresses
Deploy network monitoring solutions to detect anomalous outbound connections from the elecV2P server to internal resources
Configure intrusion detection systems (IDS) to alert on SSRF attack patterns targeting the application

Monitoring Recommendations

Enable comprehensive logging for all requests to the /mock endpoint, including full request parameters
Set up alerts for any outbound connections from the web server to internal network segments or cloud metadata services
Implement real-time monitoring of DNS queries from the elecV2P server for resolution of internal hostnames
Review access logs regularly for patterns indicative of SSRF exploitation attempts

How to Mitigate CVE-2026-5016

Immediate Actions Required

Restrict network egress from the elecV2P server to only required external destinations using firewall rules
Implement URL allowlisting in front of the vulnerable endpoint to permit only known-safe external URLs
Consider disabling the /mock endpoint if it is not required for production functionality
Deploy a Web Application Firewall (WAF) configured to block SSRF attack patterns

Patch Information

As of the last update on 2026-03-30, no official patch has been released by the elecV2P project maintainers. The vulnerability was reported through GitHub Issue #202, but the project has not responded. Users are advised to monitor the elecV2P GitHub repository for updates and apply patches as soon as they become available. In the meantime, implement the workarounds described below to reduce exposure.

Workarounds

Block access to the /mock endpoint from untrusted networks using web server configuration or reverse proxy rules
Implement input validation at the network perimeter to filter requests containing internal IP addresses or localhost references
Use network segmentation to isolate the elecV2P server from sensitive internal resources
Consider deploying the application behind a reverse proxy that strips or validates URL parameters before forwarding requests

bash

# Example nginx configuration to restrict access to vulnerable endpoint
location /mock {
    # Deny all external access to the vulnerable endpoint
    deny all;
    # Or restrict to trusted IP ranges only
    # allow 192.168.1.0/24;
    # deny all;
}