CVE-2026-25310: Extend Link SSRF Vulnerability

CVE-2026-25310 Overview

A Server-Side Request Forgery (SSRF) vulnerability has been identified in the Alobaidi Extend Link WordPress plugin. This security flaw allows attackers to manipulate server-side requests, potentially enabling them to access internal resources, bypass security controls, or interact with internal services that should not be externally accessible.

Critical Impact

Attackers with low-privilege access can exploit this SSRF vulnerability to forge requests from the vulnerable server, potentially accessing internal network resources, cloud metadata services, or sensitive internal APIs.

Affected Products

• Alobaidi Extend Link (extend-link) plugin versions up to and including 2.0.0
• WordPress installations running the vulnerable plugin versions

Discovery Timeline

• 2026-02-19 - CVE-2026-25310 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2026-25310

Vulnerability Analysis

This vulnerability is classified as CWE-918 (Server-Side Request Forgery). SSRF vulnerabilities occur when an application can be induced to make HTTP requests to an arbitrary domain of the attacker's choosing. In the context of the Extend Link WordPress plugin, the vulnerability allows authenticated attackers to craft malicious requests that the server will execute on their behalf.

The changed scope characteristic of this vulnerability indicates that a successful exploit could impact resources beyond the vulnerable component itself, potentially affecting other systems or services within the internal network infrastructure.

Root Cause

The root cause of this vulnerability stems from insufficient validation and sanitization of user-supplied URLs or endpoints within the Extend Link plugin. When the plugin processes link-related functionality, it fails to properly validate destination URLs before making server-side requests. This allows attackers to specify arbitrary URLs, including internal network addresses, localhost services, or cloud metadata endpoints.

Attack Vector

The attack requires network access and low-privilege authentication to the WordPress installation. Once authenticated, an attacker can supply a malicious URL parameter that the vulnerable plugin will process, causing the server to make HTTP requests to attacker-specified destinations.

Common exploitation scenarios include:

• Accessing cloud instance metadata services (e.g., 169.254.169.254 on AWS, Azure, or GCP)
• Scanning internal network ports and services
• Bypassing IP-based access controls to reach internal applications
• Exfiltrating sensitive configuration data from internal services

The high attack complexity rating indicates that successful exploitation may require specific conditions or additional reconnaissance to achieve meaningful impact.

Detection Methods for CVE-2026-25310

Indicators of Compromise

• Unusual outbound HTTP requests from the web server to internal IP ranges (e.g., 10.x.x.x, 172.16.x.x, 192.168.x.x)
• HTTP requests targeting cloud metadata endpoints such as 169.254.169.254
• Unexpected network connections from the WordPress server to localhost services (ports 6379, 27017, 3306, etc.)
• Log entries showing the Extend Link plugin processing requests with internal or suspicious URLs

Detection Strategies

• Monitor web server logs for requests to the Extend Link plugin with URL parameters containing internal IP addresses or hostnames
• Implement network-level monitoring to detect outbound connections from web servers to internal infrastructure
• Use Web Application Firewall (WAF) rules to detect and block SSRF patterns in request parameters
• Deploy intrusion detection rules targeting common SSRF payloads and cloud metadata access patterns

Monitoring Recommendations

• Enable verbose logging for the WordPress application to capture all plugin activity
• Configure network egress monitoring on web servers to detect anomalous internal network access
• Set up alerts for any HTTP traffic from web servers to cloud metadata IP ranges
• Review WordPress audit logs for suspicious plugin usage patterns by authenticated users

How to Mitigate CVE-2026-25310

Immediate Actions Required

• Identify all WordPress installations running the Extend Link plugin version 2.0.0 or earlier
• Disable or remove the Extend Link plugin until a patched version is available
• Implement WAF rules to block SSRF attack patterns targeting this plugin
• Restrict network egress from web servers to only necessary external destinations

Patch Information

At the time of publication, no official patch has been confirmed. Users should monitor the Patchstack SSRF Vulnerability Advisory for updates on vendor remediation efforts. Consider removing the plugin entirely if link extension functionality is not critical to your WordPress deployment.

Workarounds

• Disable the Extend Link plugin completely until a security update is released
• Implement network-level controls to prevent the web server from accessing internal IP ranges
• Use a Web Application Firewall to filter and validate URL parameters before they reach the plugin
• Restrict plugin functionality to administrator-only access if disabling entirely is not feasible
• Configure firewall rules to block outbound connections to cloud metadata services from web server hosts

# Example iptables rules to block common SSRF targets from web server
# Block access to cloud metadata endpoints
iptables -A OUTPUT -d 169.254.169.254 -j DROP

# Block access to common internal network ranges (adjust as needed)
iptables -A OUTPUT -d 10.0.0.0/8 -p tcp --dport 80 -j DROP
iptables -A OUTPUT -d 10.0.0.0/8 -p tcp --dport 443 -j DROP
iptables -A OUTPUT -d 172.16.0.0/12 -p tcp --dport 80 -j DROP
iptables -A OUTPUT -d 192.168.0.0/16 -p tcp --dport 80 -j DROP