CVE-2026-24557: Contact Form 7 GetResponse Extension Flaw

CVE-2026-24557 Overview

CVE-2026-24557 is a Sensitive Data Exposure vulnerability affecting the Contact Form 7 GetResponse Extension WordPress plugin developed by WEN Solutions. The vulnerability stems from improper handling of sensitive information (CWE-201: Insertion of Sensitive Information Into Sent Data), which allows unauthenticated attackers to retrieve embedded sensitive data from the affected plugin.

This vulnerability affects all versions of the Contact Form 7 GetResponse Extension plugin from initial release through version 1.0.8. Websites using this plugin to integrate Contact Form 7 with GetResponse email marketing services may inadvertently expose sensitive configuration data or user information to unauthorized parties.

Critical Impact

Unauthenticated attackers can remotely extract sensitive data from WordPress sites running vulnerable versions of the Contact Form 7 GetResponse Extension plugin, potentially exposing API keys, user data, or configuration information.

Affected Products

• Contact Form 7 GetResponse Extension plugin version 1.0.8 and earlier
• WordPress websites using the contact-form-7-getresponse-extension plugin
• Sites integrating Contact Form 7 with GetResponse email marketing platform

Discovery Timeline

• 2026-01-23 - CVE-2026-24557 published to NVD
• 2026-01-26 - Last updated in NVD database

Technical Details for CVE-2026-24557

Vulnerability Analysis

This vulnerability is classified as CWE-201 (Insertion of Sensitive Information Into Sent Data), indicating that the plugin improperly includes sensitive information in data transmissions or responses that can be accessed by unauthorized parties. The vulnerability exists in how the Contact Form 7 GetResponse Extension handles and transmits configuration data or user submissions.

The plugin is designed to bridge Contact Form 7 submissions with GetResponse email marketing services. During this integration process, sensitive information such as API credentials, user-submitted form data, or internal configuration details may be exposed through improper data handling practices.

The network-based attack vector with low complexity means attackers can exploit this vulnerability remotely without requiring authentication or user interaction, making it accessible to opportunistic attackers scanning for vulnerable WordPress installations.

Root Cause

The root cause of CVE-2026-24557 lies in the plugin's failure to properly sanitize or restrict sensitive information before including it in sent data. This typically occurs when:

• API keys or authentication tokens are exposed in client-side responses
• Debug information containing sensitive configuration data is not properly stripped in production
• Form submission responses inadvertently include internal data not intended for external consumption
• Plugin settings or configuration values are accessible through predictable endpoints

The CWE-201 classification indicates that the developers did not implement adequate data filtering mechanisms to prevent sensitive information from being transmitted to unintended recipients.

Attack Vector

The attack can be executed remotely over the network without any authentication requirements. An attacker would:

1. Identify WordPress sites running the vulnerable Contact Form 7 GetResponse Extension plugin
2. Craft requests to trigger the sensitive data exposure condition
3. Analyze responses to extract embedded sensitive information
4. Potentially leverage exposed data (such as API keys) for further attacks

Since no user interaction is required and the attack complexity is low, this vulnerability is easily exploitable by automated scanning tools and opportunistic attackers.

Detection Methods for CVE-2026-24557

Indicators of Compromise

• Unusual requests to WordPress plugin endpoints associated with Contact Form 7 GetResponse Extension
• Unexpected access patterns to plugin configuration or settings pages
• Evidence of API key extraction or unauthorized GetResponse API usage
• Anomalous outbound traffic from WordPress installations to unknown destinations

Detection Strategies

• Monitor WordPress access logs for suspicious requests targeting the contact-form-7-getresponse-extension plugin directory
• Implement Web Application Firewall (WAF) rules to detect and block reconnaissance attempts against plugin endpoints
• Deploy file integrity monitoring to detect unauthorized changes to plugin files
• Review GetResponse API usage logs for unauthorized access attempts using potentially compromised credentials

Monitoring Recommendations

• Enable comprehensive logging for WordPress plugin activity and API interactions
• Set up alerts for unusual patterns of requests to form submission endpoints
• Monitor for bulk data retrieval attempts that may indicate automated exploitation
• Track GetResponse API key usage for signs of credential compromise

How to Mitigate CVE-2026-24557

Immediate Actions Required

• Update the Contact Form 7 GetResponse Extension plugin to a patched version when available from WEN Solutions
• Temporarily deactivate the plugin if no patch is available and the functionality is not critical
• Rotate any API keys or credentials configured within the plugin as a precautionary measure
• Review server logs for evidence of prior exploitation attempts

Patch Information

Organizations should monitor the official WordPress plugin repository and Patchstack Vulnerability Report for patch availability. Until a patch is released, implement the workarounds described below to reduce exposure risk.

Workarounds

• Deactivate and remove the Contact Form 7 GetResponse Extension plugin if not essential to operations
• Implement server-level access controls to restrict access to plugin endpoints
• Use a Web Application Firewall (WAF) to filter requests targeting the vulnerable plugin
• Consider alternative GetResponse integration methods that do not rely on the vulnerable plugin
• Apply the principle of least privilege to GetResponse API keys used with WordPress

# WordPress CLI commands to manage the vulnerable plugin
# List installed plugins and check version
wp plugin list --name=contact-form-7-getresponse-extension --fields=name,status,version

# Deactivate the vulnerable plugin temporarily
wp plugin deactivate contact-form-7-getresponse-extension

# Check for available updates
wp plugin update --dry-run contact-form-7-getresponse-extension