PHP security vulnerabilities, October 2026

Overview

Following the disclosure of critical security vulnerabilities affecting PHP, a widely used programming language underpinning many web applications, Melo has undertaken a review of its platform and supporting infrastructure to assess potential exposure and implement the necessary security measures.

Our technical team implemented the relevant security updates on 21 October 2026. Additional protective measures had already been introduced through Cloudflare before the security patches became available.

1. Before patch releaseCloudflare WAF protections introduced
2. 21 October 2026PHP runtime and application security updates deployed
3. 22 October 2026Customers informed and this advisory published
4. In progressSecurity log review and runtime version confirmation

We recognise the importance of providing clear and transparent security assurance, particularly to our NHS and healthcare customers. This advisory outlines our assessment, remediation activities, security controls and ongoing monitoring arrangements.

01Background and nature of the vulnerabilities

The recently disclosed vulnerabilities relate to PHP, the programming language used by many web applications, including those developed using the Laravel framework.

Certain vulnerabilities may allow remote code execution (RCE) under specific conditions, potentially enabling an attacker to execute unauthorised commands on an affected server.

The potential impact depends on the affected PHP version, the application's configuration, its exposure to external traffic and the security controls in place.

Melo uses PHP as part of its core application architecture and therefore reviewed its exposure promptly following disclosure.

02Melo's PHP usage and infrastructure

The Melo clinical platform is built using Laravel and operates within a managed cloud environment.

Application

Melo clinical platform

Application framework

Laravel

PHP runtime

PHP 8.4

Hosting and runtime management

Laravel Cloud

Web application firewall

Cloudflare

Application monitoring

Laravel Nightwatch

Other PHP-based systems

None identified

The underlying PHP runtime is managed through Laravel Cloud.

The runtime was updated on 21 October 2026, alongside the relevant application security updates. Confirmation of the precise deployed PHP patch version is being obtained from the hosting provider.

Our assessment has not identified additional applications, management platforms, monitoring tools or supporting infrastructure using PHP on behalf of customers.

03Exposure and impact assessment

Our technical team assessed Melo's exposure to the disclosed vulnerabilities, including the potential impact on internet-facing services.

Vulnerability exposure

No systems have been identified as remaining vulnerable following remediation.

Before the relevant patches became available, Cloudflare introduced Web Application Firewall (WAF) protections designed to mitigate exploitation of the disclosed vulnerabilities.

These protections provided an additional layer of defence for internet-facing application traffic during the period before patch deployment.

Evidence of exploitation or compromise

As part of routine security monitoring, two suspicious requests were identified through Laravel Nightwatch on 21 October 2026.

Both requests were investigated and determined to be harmless.

An additional in-depth review of security logs and monitoring data is being undertaken as a precautionary measure.

Impact on customer services and data

We have identified:

• No disruption to Melo's clinical services attributable to these vulnerabilities.
• No evidence of unauthorised access to customer or patient data.
• No evidence of compromise affecting the confidentiality, integrity or availability of patient information.
• No requirement for customers to change their access arrangements or take remedial action.

Melo continues to operate normally.

04Remediation actions completed

The technical team implemented the relevant updates on 21 October 2026. The remediation process included the following measures:

Post-update security verification has confirmed successful deployment of the updates.

The remaining activities are additional assurance checks rather than known unresolved vulnerabilities.

05Current security posture

Following the remediation activities, Melo's current residual risk assessment is Low, subject to completion of the final security log review.

This assessment reflects:

• The deployment of the updated PHP runtime and relevant application security updates.
• Completion of remediation across 100% of identified affected assets.
• Existing Cloudflare WAF protections against relevant attack patterns.
• Ongoing security monitoring through Cloudflare and Laravel Nightwatch.
• No evidence of successful exploitation or compromise identified to date.
• Successful post-update deployment and security verification.

Our security posture will continue to be reviewed as additional technical information becomes available.

Remaining activities

Two additional assurance activities remain underway:

Should either activity identify a material change to our current assessment, we will take appropriate action and update affected customers as necessary.

06Customer guidance and communication

Melo proactively issued a security communication to customers on 22 October 2026, confirming the actions taken and our assessment of the platform's security status.

Customers can continue using Melo as normal, with no changes required to their accounts, integrations or existing workflows.

We understand that healthcare organisations may need additional assurance for internal information governance, cybersecurity or supplier-risk management processes.

This advisory is intended to provide a consistent, transparent account of our response and may be shared with relevant internal stakeholders.

07Ongoing monitoring and commitment to security

Protecting the sensitive information entrusted to Melo is fundamental to our responsibilities as a healthcare technology provider.

We continue to monitor relevant security advisories, vendor updates and application activity to ensure that appropriate protections remain in place.

Where new information or additional remediation requirements emerge, our technical team will assess these promptly and take proportionate action.

We will update this advisory if our security assessment materially changes or when outstanding verification activities have been completed.

Summary

Last updated: 22 October 2026.

Melo reserves the right to update this advisory as further information becomes available or additional verification activities are completed.