CVE-2025-31125 is a vulnerability in the Vite frontend tooling framework, which is widely used for JavaScript application development. The flaw involves the exposure of sensitive information due to improper handling of file imports when the Vite development server is exposed to the network. Specifically, when the server is started with the --host option or configured with server.host to be accessible externally, attackers can exploit query parameters (?inline&import or ?raw?import) to retrieve contents of files that should not be accessible. This can lead to unauthorized disclosure of sensitive source code, configuration files, or other internal data. The vulnerability affects multiple versions of Vite prior to the patched releases 6.2.4, 6.1.3, 6.0.13, 5.4.16, and 4.5.11. The CVSS 3.1 score is 5.3 (medium), reflecting network attack vector, high complexity, no privileges required, but user interaction needed, and impact limited to confidentiality. No known exploits have been reported in the wild yet. The root cause relates to CWE-200 (Exposure of Sensitive Information) and CWE-284 (Improper Access Control). The vulnerability primarily impacts development environments where the dev server is exposed externally, which is not a default configuration but can occur due to misconfiguration or intentional exposure for remote development. Attackers can leverage this to gain access to sensitive files, potentially aiding further attacks or intellectual property theft.

For European organizations, the primary impact is the unauthorized disclosure of sensitive information such as source code, environment variables, or internal configuration files during development. This can lead to intellectual property theft, leakage of secrets (API keys, credentials), and increased risk of subsequent targeted attacks. Since the vulnerability requires the Vite dev server to be exposed externally, organizations using remote development setups or cloud-based development environments are particularly at risk. The confidentiality breach can undermine trust, cause compliance issues with data protection regulations like GDPR, and lead to financial and reputational damage. However, the vulnerability does not allow code execution or integrity modification, limiting the scope to confidentiality impact only. The medium severity reflects the moderate risk, but the ease of exploitation in misconfigured environments makes it a relevant concern for software development teams.

1. Upgrade all Vite instances to the fixed versions: 6.2.4, 6.1.3, 6.0.13, 5.4.16, or 4.5.11 as appropriate. 2. Avoid exposing the Vite development server to external networks unless absolutely necessary. Use localhost-only binding or VPNs for remote access. 3. Implement strict network access controls and firewall rules to restrict access to development servers. 4. Review and audit development environment configurations regularly to detect unintended exposure. 5. Use environment variable management and secrets vaults to avoid embedding sensitive data in files accessible by Vite. 6. Educate developers about secure configuration practices and the risks of exposing dev servers. 7. Monitor network traffic and logs for suspicious access attempts to development servers. 8. Consider containerizing or sandboxing development environments to isolate them from production networks.