X-Powered-By: a header worth removing

The header exists because frameworks add it by default, not because anything reads it. No client changes behaviour based on the value, no cache keys on it, and no specification mentions it. It is one line of self promotion that ships on every response your service ever sends.

The cost is disclosure. A version number here tells a scanner which published vulnerabilities to try before it sends a probe, and even without a version the product name narrows the search considerably. That is not a serious defence on its own, but it is free to remove and it takes your site out of results built by matching on this header.

Removing it is usually one setting or one line of middleware, and it is worth doing at the same time as trimming the Server header, since leaving one and removing the other achieves very little. Check what else your stack adds by default while you are there: several frameworks emit their own version or generator headers with the same problem.

Do not overstate the benefit. Response header order, cookie naming, error page wording and default asset paths still identify most stacks to anyone looking properly. Removing the header is tidying that closes an easy automated match, and the patching underneath it is what actually matters.

It is also worth checking from outside rather than from the code. Application gateways, security appliances and hosting platforms all add headers of their own, so a service that sends nothing itself can still arrive at the client with a product name attached. The response as your visitors receive it is the only version that counts.