What does UDP port 53 do?

What does UDP port 53 do?

The DNS uses TCP Port 53 for zone transfers, for maintaining coherence between the DNS database and the server. The UDP protocol is used when a client sends a query to the DNS server. The TCP protocol should not be used for queries as it gives a lot of information, which is useful to attackers.

Is port 53 TCP or UDP?

DNS
The answer is DNS is mostly UDP Port 53, but as time progresses, DNS will rely on TCP Port 53 more heavily.

Is DNS port 53 secure?

But what many CIOs and their likes don’t realize is that traditional security measures typically don’t enough protection against DNS attacks because they leave port 53 in the firewall open. The malware was inside the system for six months exfiltrating data through DNS before anyone realized what was going on.

Why do we filter on port 53?

Zone transfers take place over TCP port 53 and in order to prevent our DNS servers from divulging critical information to attackers, TCP port 53 is typically blocked.

How do I know if my port 53 is blocked?

Check for Blocked Port using the Command Prompt

1. Type cmd in the search bar.
2. Right-click on the Command Prompt and select Run as Administrator.
3. In the command prompt, type the following command and hit enter. netsh firewall show state.
4. This will display all the blocked and active port configured in the firewall.

What is the protocol for port 53?

Service Name and Transport Protocol Port Number Registry

What is listening on port 53?

Description: “DNS” is the glue that translates human-readable domain and machine names like “grc.com” or “amazon.com” into their machine-readable Internet Protocol (IP) address equivalents. DNS servers listen on port 53 for queries from DNS clients.

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