Facebook Google Plus Twitter LinkedIn YouTube RSS Menu Search Resource - BlogResource - WebinarResource - ReportResource - Eventicons_066 icons_067icons_068icons_069icons_070

Critical OS Command Injection Vulnerability in Citrix SD-WAN Center Discovered

Tenable Research has discovered a critical vulnerability in Citrix SD-WAN Center that could lead to remote code execution.

Background

On April 10, Citrix released a security bulletin for CVE-2019-10883, an operating system (OS) command injection vulnerability in Citrix SD-WAN Center 10.2.x before 10.2.1 and NetScaler SD-WAN Center 10.0.x before 10.0.7. Tenable Research discovered this vulnerability while developing a plugin for CVE-2017-6316 and reported it to Citrix.

Citrix Netscaler SD-WAN (software defined wide-area network) allows enterprises to manage their networks and create a virtual WAN. These types of products are used to support branch offices and remote data centers, and to maintain connectivity for cloud-based applications. According to the Citrix website, Netscaler SD-WAN is used in several industries like shipping, non-profit, hospitality and others.

Analysis

While reviewing CTX236992, Tenable Research observed that most of the vulnerabilities in this security bulletin required authentication. For the purpose of writing an uncredentialed Nessus plugin, we ended up looking at two unauthenticated command injection vulnerabilities mentioned in the writeup by the researchers who were credited in CTX236992. These vulnerabilities appeared to be linked to CVE-2017-6316, a vulnerability in the Citrix SD-WAN appliance.

Through our research of CVE-2017-6316, we discovered the Citrix SD-WAN Center 10.2.0.136.733315 was vulnerable to insufficient validation of user-supplied data ($username) in the controller located at /home/talariuser/www/app/Controller/UsersController.php (CVE-2019-10883).

Proof of concept

An unauthenticated remote attacker could exploit this vulnerability to execute arbitrary commands with root privileges. This could be achieved by running the following cURL command:

curl -skv --tlsv1.2 -d '_method=POST&data%5BUser%5D%5Busername%5D=%60sudo%20id%20>/tmp/test%60&data%5BUser%5D%5Bpassword%5D=my_password&data%5BUser%5D%5BsecPassword%5D=my_secPassword' 'https://[target_host]/login'

The output from running this command:

[email protected]:/home/talariuser/www/app/Controller# cat /tmp/test

uid=0(root) gid=0(root) groups=0(root)

Vendor response

Tenable Research contacted Citrix in early February and confirmed they reproduced the vulnerability by the end of February. Citrix published its security bulletin for this vulnerability on April 10.

Solution

Users should upgrade to Citrix SD-WAN Center 10.2.1 or later and NetScaler SD-WAN Center 10.0.7 or later. Additionally, Citrix provided a list of best practices that should be used to harden the security of the SD-WAN Center.

Get more information

Learn more about Tenable, the first Cyber Exposure platform for holistic management of your modern attack surface.

Get a free 60-day trial of Tenable.io Vulnerability Management.

Subscribe to the Tenable Blog

Subscribe
Try for Free Buy Now

Try Tenable.io

FREE FOR 30 DAYS

Enjoy full access to a modern, cloud-based vulnerability management platform that enables you to see and track all of your assets with unmatched accuracy. Sign up now.

Buy Tenable.io

Enjoy full access to a modern, cloud-based vulnerability management platform that enables you to see and track all of your assets with unmatched accuracy. Purchase your annual subscription today.

65 assets

$2,275

Buy Now

Try for Free Buy Now

Try Nessus Professional Free

FREE FOR 7 DAYS

Nessus® is the most comprehensive vulnerability scanner on the market today. Nessus Professional will help automate the vulnerability scanning process, save time in your compliance cycles and allow you to engage your IT team.

Buy Nessus Professional

Nessus® is the most comprehensive vulnerability scanner on the market today. Nessus Professional will help automate the vulnerability scanning process, save time in your compliance cycles and allow you to engage your IT team.

Buy a multi-year license and save. Add Advanced Support for access to phone, email, community and chat support 24 hours a day, 365 days a year. Full details here.

Try for Free Buy Now

Try Tenable.io Web Application Scanning

FREE FOR 30 DAYS

Enjoy full access to our latest web application scanning offering designed for modern applications as part of the Tenable.io platform. Safely scan your entire online portfolio for vulnerabilities with a high degree of accuracy without heavy manual effort or disruption to critical web applications. Sign up now.

Buy Tenable.io Web Application Scanning

Enjoy full access to a modern, cloud-based vulnerability management platform that enables you to see and track all of your assets with unmatched accuracy. Purchase your annual subscription today.

5 FQDNs

$3,578

Buy Now

Try for Free Contact Sales

Try Tenable.io Container Security

FREE FOR 30 DAYS

Enjoy full access to the only container security offering integrated into a vulnerability management platform. Monitor container images for vulnerabilities, malware and policy violations. Integrate with continuous integration and continuous deployment (CI/CD) systems to support DevOps practices, strengthen security and support enterprise policy compliance.

Buy Tenable.io Container Security

Tenable.io Container Security seamlessly and securely enables DevOps processes by providing visibility into the security of container images – including vulnerabilities, malware and policy violations – through integration with the build process.

Learn More about Industrial Security

Get a Demo of Tenable.sc

Please fill out the form below with your contact information and a sales representative will contact you shortly to schedule a demo. You may also include a short comment (limited to 255 characters). Please note that fields with asterisks (*) are mandatory.

Try for Free Contact Sales

Try Tenable Lumin

FREE FOR 30 DAYS

Visualize and explore your Cyber Exposure, track risk reduction over time and benchmark against your peers with Tenable Lumin.

Buy Tenable Lumin

Contact a Sales Representative to see how Lumin can help you gain insight across your entire organization and manage cyber risk.