Torgeek
| Vulnerability Name: | DNS Bypass Firewall Rules (UDP 53) |
|---|---|
| Category: | Firewalls |
| Type: | Attack |
| Summary: | It is possible to by-pass the rules of the remote firewall by sending UDP packets with a source port equal to 53. An attacker may use this flaw to inject UDP packets to the remote hosts, in spite of the presence of a firewall. |
- Is port 53 vulnerable?
- Can port 53 be exploited?
- What is port 53 used for?
- Should port 53 be open?
- Is port 53 well known?
- Why is port 53 blocked?
- Is port 53 encrypted?
- Should I close port 53?
- Should I close port 53?
- Is port 53 encrypted?
- Is route53 a protective DNS service?
- What are unsafe ports?
- Which ports are considered insecure?
Is port 53 vulnerable?
Port 53 (DNS)
This port is particularly vulnerable to DDoS attacks.
Can port 53 be exploited?
By sending specially-crafted DNS packets to TCP port 53, a remote attacker could exploit this vulnerability to cause the device to reload. haneWIN DNS Server is vulnerable to a denial of service attack. A remote attacker could send a large amount of data to port 53 and cause the server to crash.
What is port 53 used for?
DNS uses Port 53 which is nearly always open on systems, firewalls, and clients to transmit DNS queries. Rather than the more familiar Transmission Control Protocol (TCP) these queries use User Datagram Protocol (UDP) because of its low-latency, bandwidth and resource usage compared TCP-equivalent queries.
Should port 53 be open?
Port 53 is open for DNS. Why would I need this? You need to have UDP 53 allowed for responses to DNS queries that your server sends, as UDP is a stateless protocol. Don't block it if you want any kind of outbound connectivity, software updates, etc.
Is port 53 well known?
The well-known port number for DNS is 53, and that's where the server process should be listening for client requests.
Why is port 53 blocked?
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.
Is port 53 encrypted?
The UDP source port is 53 which is the standard port number for unencrypted DNS. The UDP payload is therefore likely to be a DNS answer. That suggests that the source IP address 192.168.
Should I close port 53?
You don't need to block port 53 on your router, but you do need to spot which one of your computers is generating this traffic. I would recommend downloading Avast or AVG (Free) together with Malwarebytes (also free) on all the PC's in your network and I'm positive you will find the culprit.
Should I close port 53?
You don't need to block port 53 on your router, but you do need to spot which one of your computers is generating this traffic. I would recommend downloading Avast or AVG (Free) together with Malwarebytes (also free) on all the PC's in your network and I'm positive you will find the culprit.
Is port 53 encrypted?
The UDP source port is 53 which is the standard port number for unencrypted DNS. The UDP payload is therefore likely to be a DNS answer. That suggests that the source IP address 192.168.
Is route53 a protective DNS service?
You can protect your domain from this type of attack, known as DNS spoofing or a man-in-the-middle attack, by configuring Domain Name System Security Extensions (DNSSEC), a protocol for securing DNS traffic. Amazon Route 53 supports DNSSEC signing as well as DNSSEC for domain registration.
What are unsafe ports?
A port or berth will be unsafe if the ship is unable to reach the port safely. For example a port may be considered unsafe even if the ship suffers damage during its passage on a river or channel when approaching a port.
Which ports are considered insecure?
Examples of insecure services, protocols, or ports include but are not limited to FTP, Telnet, POP3, IMAP, and SNMP v1 and v2.
