CVE-2026-39645 Overview
A Server-Side Request Forgery (SSRF) vulnerability has been identified in the GlobalPayments WooCommerce plugin for WordPress. This vulnerability allows attackers to manipulate server-side requests, potentially enabling them to access internal resources, bypass security controls, and interact with internal services that should not be externally accessible.
Critical Impact
This SSRF vulnerability could allow attackers to probe internal network infrastructure, access sensitive internal services, bypass firewall restrictions, and potentially pivot to further attacks within the organization's infrastructure.
Affected Products
- GlobalPayments WooCommerce plugin versions up to and including 1.18.0
- WordPress installations running the vulnerable plugin versions
- WooCommerce-based e-commerce sites using GlobalPayments integration
Discovery Timeline
- 2026-04-08 - CVE-2026-39645 published to NVD
- 2026-04-08 - Last updated in NVD database
Technical Details for CVE-2026-39645
Vulnerability Analysis
The vulnerability exists within the GlobalPayments WooCommerce plugin, a payment gateway integration for WooCommerce-powered WordPress sites. 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 payment processing plugins, this is particularly concerning as these components typically have elevated network privileges to communicate with payment processors.
The flaw is classified under CWE-918 (Server-Side Request Forgery), which describes scenarios where an attacker can supply or modify a URL that the code running on the server will read or submit data to. This vulnerability affects all versions of the GlobalPayments WooCommerce plugin from the initial release through version 1.18.0.
Root Cause
The root cause of this vulnerability is insufficient validation of user-supplied URLs or endpoints within the plugin's request handling mechanisms. The plugin fails to properly validate, sanitize, or restrict the destination of server-side HTTP requests, allowing attackers to redirect these requests to arbitrary internal or external destinations. This typically occurs in payment callback handlers, webhook processors, or API endpoint configurations where URL parameters are accepted without adequate security controls.
Attack Vector
An attacker can exploit this SSRF vulnerability by crafting malicious requests that manipulate URL parameters or endpoint configurations within the plugin. The attack typically involves:
- Identifying input fields or parameters that influence server-side request destinations
- Injecting URLs pointing to internal resources (e.g., localhost, 127.0.0.1, internal IP ranges, or cloud metadata endpoints)
- Using the compromised server as a proxy to access protected internal services
The vulnerability mechanism involves the plugin accepting user-controlled input that influences the destination of HTTP requests made by the server. When the plugin processes payment-related operations, it may make outbound requests to URLs that can be manipulated by an attacker. This allows the attacker to force the server to make requests to internal network resources, cloud infrastructure metadata services (such as AWS IMDSv1 at 169.254.169.254), or other sensitive endpoints.
For detailed technical information, refer to the Patchstack Vulnerability Report.
Detection Methods for CVE-2026-39645
Indicators of Compromise
- Unusual outbound HTTP requests from the WordPress server to internal IP addresses or cloud metadata endpoints
- Web server logs showing requests with suspicious URL parameters targeting internal resources
- Unexpected responses or data from internal services appearing in application logs
- Network traffic to 169.254.169.254 (cloud metadata) or RFC 1918 private IP ranges originating from the web server
Detection Strategies
- Monitor web application firewall (WAF) logs for SSRF attack patterns including requests containing internal IP addresses or localhost references
- Implement network-level monitoring for outbound connections from web servers to internal resources or cloud metadata services
- Review WordPress and WooCommerce plugin access logs for anomalous request patterns to the GlobalPayments plugin endpoints
- Deploy intrusion detection rules to identify SSRF payload signatures in HTTP request parameters
Monitoring Recommendations
- Configure alerting for outbound connections from web servers to RFC 1918 private IP ranges
- Monitor for DNS lookups of internal hostnames from public-facing WordPress instances
- Implement logging of all outbound HTTP requests made by the GlobalPayments WooCommerce plugin
- Track failed authentication attempts and unusual API response patterns from the payment gateway integration
How to Mitigate CVE-2026-39645
Immediate Actions Required
- Update the GlobalPayments WooCommerce plugin to the latest available version that addresses this vulnerability
- Audit WordPress installations for the presence of vulnerable plugin versions (1.18.0 and below)
- Implement network segmentation to restrict the WordPress server's ability to make requests to internal resources
- Deploy Web Application Firewall (WAF) rules to block common SSRF attack patterns
Patch Information
Organizations should update to the latest version of the GlobalPayments WooCommerce plugin that addresses this SSRF vulnerability. Check the official WordPress plugin repository or the vendor's official channels for security updates. Until a patch is applied, implement the workarounds below to reduce exposure.
For additional patch details, consult the Patchstack Vulnerability Report.
Workarounds
- Temporarily disable the GlobalPayments WooCommerce plugin if not actively required for business operations
- Implement strict egress filtering at the network level to prevent the web server from accessing internal resources
- Use a reverse proxy or WAF to inspect and block requests containing SSRF payloads
- Consider switching to an alternative payment gateway plugin until the vulnerability is remediated
# Example: Network-level mitigation using iptables to block requests to internal networks
# Block outbound connections to common internal IP ranges from the web server
iptables -A OUTPUT -d 10.0.0.0/8 -j DROP
iptables -A OUTPUT -d 172.16.0.0/12 -j DROP
iptables -A OUTPUT -d 192.168.0.0/16 -j DROP
iptables -A OUTPUT -d 169.254.169.254 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
