Your server tells which software and which version it runs. An attacker immediately sees which known holes to try.
Bots scan the web for servers with a version that has a known hole. Leaving out the version number does not fix a hole, but it makes your site harder to find in such a search.
This is part of the security check, a separate check next to the crawl, in Studio and Bureau, and only on a site you have verified. Snaglist only looks at what any visitor can see from outside. It never logs in, guesses no passwords and sends no attacks. It reads the Server and X-Powered-By headers of the homepage and reports them when they include a version number.
In the report for your client this appears under the heading "Your server tells which software and version it runs". When everything is in order, the report says: "The server does not reveal its software version".
Snaglist checks every page of your site, for this issue and all the others. Start for free, no credit card needed.
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