Report: DNS Cache Poisoning Attack

[idealeer]

We found that SmartDNS does not use randomization for the source port in DNS queries, which makes it susceptible to cache poisoning attacks.

[Ryu-Z]

Use a fixed port?

[PikuZheng]

Use a fixed port?

yes. only change port while reconnect

[pymumu]

Currently, only one port number will be used for communication, and no random port number be used.

The latest code adds some processing to determine the communication source IP, port, and destination IP port. If these IP/port are different, the data will be discarded, which can avoid some problems to a certain extent.