CVE-2026-25146: OpenEMR Information Disclosure Flaw

CVE-2026-25146 Overview

CVE-2026-25146 is an information disclosure vulnerability affecting OpenEMR, a widely-used free and open source electronic health records (EHR) and medical practice management application. The vulnerability exists in versions 5.0.2 through 7.x, where sensitive gateway_api_key secret values are rendered to the client in plaintext through at least two distinct code paths. This exposure of payment gateway credentials could enable attackers to perform unauthorized financial transactions or achieve broad account takeover of integrated payment gateway APIs.

Critical Impact

Leaked payment gateway API keys could result in arbitrary money movement, unauthorized financial transactions, or complete account takeover of connected payment processing systems in healthcare environments.

Affected Products

• OpenEMR versions 5.0.2 through 7.x (before 8.0.0)
• open-emr openemr

Discovery Timeline

• 2026-03-03 - CVE-2026-25146 published to NVD
• 2026-03-04 - Last updated in NVD database

Technical Details for CVE-2026-25146

Vulnerability Analysis

This vulnerability is classified as CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor). The flaw allows authenticated users with low privileges to access sensitive payment gateway API credentials that should never be exposed to client-side code.

The vulnerability manifests in two specific PHP files within the OpenEMR codebase. The first vulnerable code path is located in the front_payment.php file within the patient interface directory. The second vulnerable path exists in the portal_payment.php file within the patient portal directory. Both files improperly render the gateway_api_key secret value directly to the client browser, making it visible in the HTML source or JavaScript context.

The attack requires network access and low-privilege authentication, but no user interaction is needed. Successful exploitation compromises both confidentiality and integrity of the payment processing systems connected to the OpenEMR installation.

Root Cause

The root cause of CVE-2026-25146 is improper handling of sensitive credentials in server-side rendering. The application fails to sanitize or exclude the gateway_api_key value when generating client-facing HTML or JavaScript content. Instead of keeping these credentials server-side only, the vulnerable code paths directly embed the API key in responses sent to the browser, violating the principle of least privilege and secure credential management practices.

Attack Vector

The attack is network-based and can be executed by any authenticated user with access to the payment processing functionality. An attacker with a low-privilege account can navigate to either the front payment interface or the patient portal payment page. By viewing the page source or inspecting network traffic, the attacker can extract the plaintext gateway_api_key. Once obtained, this credential can be used to:

1. Make unauthorized API calls directly to the payment gateway
2. Initiate arbitrary financial transactions
3. Access payment gateway administrative functions
4. Potentially pivot to other systems using the compromised credentials

The vulnerability does not require any user interaction beyond the attacker's own authentication and navigation to the affected pages.

Detection Methods for CVE-2026-25146

Indicators of Compromise

• Unusual API calls to payment gateway endpoints from unexpected IP addresses or geographic locations
• Payment gateway audit logs showing API key usage outside normal business hours or usage patterns
• Client-side requests capturing HTML content from front_payment.php or portal_payment.php pages
• Anomalous financial transactions or unauthorized payment processing activity

Detection Strategies

• Monitor payment gateway API access logs for unexpected usage patterns or authentication from new IP addresses
• Implement web application firewall (WAF) rules to detect attempts to access or scrape the vulnerable payment PHP files
• Review OpenEMR access logs for unusual patterns of access to payment-related endpoints
• Enable detailed logging on payment gateway integrations to track all API key usage

Monitoring Recommendations

• Configure alerting for any payment gateway API calls that occur outside of expected OpenEMR server IP ranges
• Implement rate limiting and anomaly detection on payment processing endpoints
• Set up real-time monitoring for changes to payment gateway account settings or configurations
• Establish baseline metrics for normal payment transaction volumes and alert on deviations

How to Mitigate CVE-2026-25146

Immediate Actions Required

• Upgrade OpenEMR to version 8.0.0 or later immediately
• Rotate all payment gateway API keys after upgrading to ensure any potentially leaked credentials are invalidated
• Review payment gateway transaction logs for any unauthorized activity during the exposure window
• Audit user access to payment-related functionality and restrict to essential personnel only

Patch Information

OpenEMR has released version 8.0.0 which addresses this vulnerability. The fix is available in commit fe6341496dc82d5b4f5a3f35891bb2e2481f3b25. Organizations should review the GitHub Security Advisory GHSA-2hq8-wc73-jvvq for complete details on the vulnerability and patch.

Workarounds

• If immediate upgrade is not possible, disable or restrict access to payment gateway integration features until patching can occur
• Implement network segmentation to limit which systems can access payment processing functionality
• Configure payment gateway accounts with IP allowlisting to restrict API access to known OpenEMR server addresses only
• Consider temporarily switching to manual payment processing workflows until the vulnerability is remediated

# After upgrading to OpenEMR 8.0.0, rotate payment gateway API keys
# Example: Update OpenEMR globals configuration with new API key
# Access Administration -> Globals -> Connectors and update gateway credentials

# Verify the upgrade version
grep -r "v_major\|v_minor\|v_patch" /var/www/html/openemr/version.php