Language: TypeScript
Label: safe
CWE: CWE-918 \u2014 Server-Side Request Forgery (SSRF)
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Code:
export const validateIP = async (ip: string, url: string) => {
	const env = getEnv();

	if (env.IMPORT_IP_DENY_LIST.includes(ip)) {
		throw new Error(`Requested URL "${url}" resolves to a denied IP address`);
	}

	if (env.IMPORT_IP_DENY_LIST.includes('0.0.0.0')) {
		const networkInterfaces = os.networkInterfaces();

		for (const networkInfo of Object.values(networkInterfaces)) {
			if (!networkInfo) continue;

			for (const info of networkInfo) {
				if (info.address === ip) {
					throw new Error(`Requested URL "${url}" resolves to a denied IP address`);
				}
			}
		}
	}
};