Critical RCE Vulnerability in React Native CLI Exposes Developers to Attacks
Executive Summary
In November 2025, a critical remote code execution (RCE) vulnerability, designated as CVE-2025-11953 and dubbed 'Metro4Shell,' was discovered in the '@react-native-community/cli' npm package. This package, integral to React Native development, had versions 4.8.0 through 20.0.0-alpha.2 affected. The flaw allowed unauthenticated attackers to execute arbitrary operating system commands on machines running the Metro Development Server, which binds to external interfaces by default. Exploitation was achieved by sending specially crafted POST requests to the '/open-url' endpoint, leading to potential full system compromise. The vulnerability was patched in version 20.0.0 released in October 2025. (github.com)
The 'Metro4Shell' incident underscores the critical importance of securing development environments and the potential risks posed by exposed development servers. It highlights the necessity for developers to regularly update dependencies, configure development tools securely, and implement network access controls to prevent unauthorized access. (csa.gov.sg)
Why This Matters Now
The 'Metro4Shell' vulnerability exemplifies the growing trend of attackers targeting development environments to gain initial access to systems. As development tools become more interconnected and accessible, ensuring their security is paramount to prevent potential supply chain attacks and unauthorized access to sensitive codebases.
Attack Path Analysis
An unauthenticated attacker exploited the Metro4Shell vulnerability (CVE-2025-11953) in the Metro Development Server to execute arbitrary commands on the host system. The attacker then escalated privileges by disabling Microsoft Defender Antivirus protections. Subsequently, the attacker moved laterally within the network by deploying a Rust-based payload with anti-analysis features. The compromised system established a raw TCP connection to an attacker-controlled server for command and control. The attacker exfiltrated sensitive data from the compromised system. Finally, the attacker executed additional malicious actions, potentially causing further disruption or damage.
Kill Chain Progression
Initial Compromise
Description
An unauthenticated attacker exploited the Metro4Shell vulnerability (CVE-2025-11953) in the Metro Development Server to execute arbitrary commands on the host system.
Related CVEs
CVE-2025-11953
CVSS 9.8The Metro Development Server in the React Native Community CLI binds to external interfaces by default, exposing an endpoint vulnerable to OS command injection, allowing unauthenticated remote attackers to execute arbitrary commands.
Affected Products:
Meta React Native Community CLI – 4.8.0 through 20.0.0-alpha.2
Exploit Status:
exploited in the wild
MITRE ATT&CK® Techniques
Exploit Public-Facing Application
Command and Scripting Interpreter: PowerShell
Command and Scripting Interpreter: Windows Command Shell
User Execution: Malicious Library
Supply Chain Compromise: Compromise Software Dependencies and Development Tools
Impair Defenses: Disable or Modify Tools
Ingress Tool Transfer
Potential Compliance Exposure
Mapping incident impact across multiple compliance frameworks.
PCI DSS 4.0 – Ensure all system components and software are protected from known vulnerabilities
Control ID: 6.2
NYDFS 23 NYCRR 500 – Cybersecurity Policy
Control ID: 500.03
DORA – ICT Risk Management Framework
Control ID: Article 5
CISA ZTMM 2.0 – Asset Management
Control ID: 2.1
NIS2 Directive – Cybersecurity Risk Management Measures
Control ID: Article 21
Sector Implications
Industry-specific impact of the vulnerabilities, including operational, regulatory, and cloud security risks.
Computer Software/Engineering
Critical Metro4Shell RCE vulnerability in React Native CLI package enables remote code execution, compromising development infrastructure and supply chain security.
Information Technology/IT
Supply chain attacks targeting npm packages expose IT infrastructure to lateral movement and data exfiltration through compromised development tools.
Financial Services
Development server vulnerabilities threaten financial applications using React Native, risking HIPAA/PCI compliance violations and encrypted traffic compromise.
Health Care / Life Sciences
Healthcare mobile applications built with affected React Native CLI face zero trust segmentation failures and potential HIPAA compliance breaches.
Sources
- Hackers Exploit Metro4Shell RCE Flaw in React Native CLI npm Packagehttps://thehackernews.com/2026/02/hackers-exploit-metro4shell-rce-flaw-in.htmlVerified
- NVD - CVE-2025-11953https://nvd.nist.gov/vuln/detail/CVE-2025-11953Verified
- CVE-2025-11953: Critical React Native Community CLI Vulnerabilityhttps://jfrog.com/blog/cve-2025-11953-critical-react-native-community-cli-vulnerabilityVerified
- Metro4Shell: Exploitation of React Native’s Metro Server in the Wildhttps://www.vulncheck.com/blog/metro4shell_eitwVerified
Frequently Asked Questions
Cloud Native Security Fabric Mitigations and ControlsCNSF
Aviatrix Zero Trust CNSF is pertinent to this incident as it could have limited the attacker's ability to move laterally and exfiltrate data by enforcing strict segmentation and controlled egress policies.
Control: Cloud Native Security Fabric (CNSF)
Mitigation: The attacker's ability to exploit the vulnerability may have been constrained by reducing the attack surface through strict segmentation and access controls.
Control: Zero Trust Segmentation
Mitigation: The attacker's ability to escalate privileges may have been limited by enforcing strict segmentation, reducing the scope of accessible systems.
Control: East-West Traffic Security
Mitigation: The attacker's lateral movement could have been constrained by monitoring and controlling east-west traffic, reducing unauthorized access.
Control: Multicloud Visibility & Control
Mitigation: The attacker's command and control communications may have been limited by monitoring and controlling outbound connections.
Control: Egress Security & Policy Enforcement
Mitigation: The attacker's data exfiltration efforts could have been constrained by enforcing strict egress policies, reducing unauthorized data transfers.
The attacker's ability to cause further disruption may have been limited by reducing the blast radius through strict segmentation and access controls.
Impact at a Glance
Affected Business Functions
- Application Development
- Software Testing
Estimated downtime: 7 days
Estimated loss: $50,000
Potential exposure of source code and development environment configurations.
Recommended Actions
Key Takeaways & Next Steps
- • Implement Zero Trust Segmentation to restrict access and limit lateral movement within the network.
- • Deploy Inline IPS (Suricata) to detect and prevent exploitation attempts targeting known vulnerabilities.
- • Utilize Cloud Firewall (ACF) to control and monitor outbound traffic, preventing unauthorized data exfiltration.
- • Enhance Threat Detection & Anomaly Response capabilities to identify and respond to suspicious activities promptly.
- • Regularly update and patch software components to mitigate known vulnerabilities like CVE-2025-11953.
