CVE-2025-56647 identifies a security vulnerability in the npm package @farmfe/core, specifically versions before 1.7.6. The vulnerability stems from the development server's WebSocket implementation used for hot module reloading, which fails to validate the origin header when establishing WebSocket connections. Normally, origin validation is a critical security control that ensures only trusted web pages can connect to the WebSocket server. Without this validation, an attacker can craft a malicious webpage that, when visited by a developer running the Farm development server, establishes a WebSocket connection to the developer's local server. Through this connection, the attacker can surveil the development environment and potentially exfiltrate source code or other sensitive information transmitted over the WebSocket. The vulnerability impacts confidentiality but does not affect integrity or availability. Exploitation requires the developer to visit a malicious webpage (user interaction) but does not require any authentication or privileges on the development server. The CVSS v3.1 score is 6.5 (medium severity), reflecting the ease of remote exploitation combined with the high confidentiality impact. No known exploits have been reported in the wild as of the publication date. The vulnerability primarily affects development environments rather than production systems, but the risk of intellectual property theft and exposure of proprietary source code is significant. Mitigation involves updating @farmfe/core to version 1.7.6 or later, which includes proper origin validation, and implementing network or firewall rules to restrict WebSocket connections to trusted origins during development.

For European organizations, the primary impact of CVE-2025-56647 is the potential theft of proprietary source code and intellectual property during the software development process. This can lead to significant competitive disadvantage, loss of trade secrets, and increased risk of further attacks if sensitive code or credentials are exposed. Since the vulnerability affects the development server used for hot module reloading, it does not directly impact production systems but compromises the confidentiality of the development environment. Organizations with active web development teams using @farmfe/core are at risk, especially if developers access untrusted websites while running the vulnerable development server. The exposure of source code could also lead to compliance issues under European data protection regulations if the code contains sensitive personal data processing logic or security controls. Additionally, the vulnerability could be leveraged by advanced persistent threat (APT) actors targeting European tech companies to gain early insight into software projects. The medium severity rating indicates a moderate but non-negligible risk that requires timely remediation to avoid intellectual property loss.

1. Upgrade @farmfe/core to version 1.7.6 or later immediately to ensure origin validation is enforced in the WebSocket implementation. 2. Restrict WebSocket connections on development servers to trusted origins only, using firewall rules or WebSocket server configuration to whitelist developer machines and trusted domains. 3. Educate developers to avoid visiting untrusted or suspicious websites while running development servers that expose WebSocket endpoints. 4. Consider isolating development environments from general internet access or using VPNs to limit exposure to malicious webpages. 5. Implement network segmentation to separate development machines from sensitive production networks. 6. Monitor WebSocket traffic during development for unusual connection attempts or data exfiltration patterns. 7. Review and audit development tooling configurations regularly to ensure security best practices are followed. 8. Employ endpoint protection solutions that can detect and block suspicious network connections initiated by development tools.