How to bypass URL filters using math

Maybe for someone it will be a discovery, but modern browsers can perceive URLs not only in the decimal system, but also in the hexadecimal and hexadecimal, and even a single 32-bit number. That is, the URL type 66.102.13.19 can be represented in several different ways.

0x42.0x66.0x0d.0x63
0x42660d63
1113984355
00000102.00000146.00000015.00000143

Click on any of the options - and go to google.com.

This technique was known for a long time , but now it seems to have forgotten about it. Worst of all, some anti-virus software vendors forgot about it, which filters mail traffic for dangerous links. They block the link in its normal form, but miss an 8, 16, or 32-bit IP address.
')
The result is obvious: a banking Trojan has already been noticed, in which these old mathematical tricks have been reanimated.

By the way, what is not an idea for cybersquatters. You can find a bunch of beautiful m free addresses in 32-bit digits, for example.

via slashdot