McAfee Researchers Exploit Smart Plug to Attack Smart TV!
Researchers from McAfee have demonstrated how a flaw in a Belkin smart switch can be used to access other connected devices on the same network as the switch.
One of the recurrent themes of Internet of Things security might be summarized as “its not the THING, stupid!” In other words: the value of the individual endpoint is irrelevant. A webcam, a baby monitor, a connected TV – none of these, by themselves, hold much sensitive information or represent much computing power. Rather, it is the value of the things in aggregate, or their ability to open a path to other, more valuable things that matters.
Now new research from McAfee is putting that to the test, by demonstrating how a flaw in a Belkin smart switch can be used to access other connected devices on the same network as the switch.
In a recent blog post, McAfee said that it has uncovered a buffer overflow flaw in a component of the Wemo Insight Smart Plug that could allow an attacker to run his or her own code on the device and use it to access and attack other devices on the same network as the smart plug.
The vulnerability, CVE-2018-6692, is in a software library known as “libUPnPHndlr.so.” The process McAfee used to discover it is lengthy and complex, with researchers disassembling and reverse engineering the Wemo Insight Smart Plug. If you want a nice write up on how to do this, including tool talk and photos, check out their blog post.
For everyone else, what’s important to know is that Wemo Insight plugs are just tiny little Linux devices, running the OpenWRT embedded Linux OS – and not a very stripped down version of OpenWRT either. The researchers found two exploitable vectors on it: a write-what-where condition allows an attacker to write data to an arbitrary location in memory; by continuing to overwrite data on the stack, an attacker can overwrite the $RA register or return address for the calling function, providing the attacker control of the execution flow.
By using Linux commands left enabled on the smart plug, the researchers found they were able to download and execute any script, run NetCat, which could allow an attacker to write a script to create a reverse shell on the device. While attacks to the device itself are limited to turning the device on or off, the potential damage grows where the plug is networked with other devices. “The plug could now be an entry point to a larger attack. Later in this report, we will look at one possible attack,” the McAfee researchers concluded.
To prove that point, the McAfee researchers developed a proof of concept attack in which a compromised plug used a built-in UPnP library to poke a hole in the network router, creating a backdoor channel for an attacker to connect remotely, unnoticed on the network.
With that access, the researchers were able to use a remote shell to control a TCL smart TV connected to the same network as the Wemo plug by exploiting a Roku API implementation on the TV that accepts unencrypted and unauthenticated HTTP GET/POST requests. “Using the Wemo as a middleman, the attacker can power the TV on and off, install or uninstall applications, and access arbitrary online content,” the researchers found.
And smart TVs are just one visible example of how the Wemo plug could be used to pivot to other devices on a network. “With the attacker having established a foothold on the network and able to open arbitrary ports, any machine connected to the network is at risk. Because attacks can be conducted through the Wemo and the port mappings generated using this exploit are not visible from the router’s administration page, the attacker’s footprint remains small and hard to detect,” the researchers concluded.
This isn’t the first time that Wemo products have been the focus of security researchers. At the 2017 Security of Things Forum, Scott Tenaglia of the firm Invincea revealed a number of security flaws in Wemo home automation devices including vulnerability to a type of attack known as SQL injection. By sending purposely mis-formed updates to WeMo devices, Tenaglia found he could create his own malicious executable that was run by the WeMo smart device, allowing him to take control of those devices.
- Application Security Analyst
- Up to £85,000 Base
An Application Security Analyst is needed for an innovative commercial organisation in London. The Application Security Analyst will be working closely with the development team and should possess a blend of application security, development languages and Information Security skills. Application Security Analyst MUST have strong interpersonal skills. The Application Security Analyst role will include, but in no way be limited to; designing solutions to maintain security, whilst incorporating design solutions in Development, DevOps and Architectural best practices. Conduct application-level penetration testing and review security architecture of Product suite. Executing projects to implement a Security strategy. Knowledge / Experience should include; penetration testing consultancy, source code reviews, vulnerability management and security assessments. Experience with the following is desirable: Agile Development, Fortify 360 SCA, IBM Rational AppScan and exposure to security industry standards - ISO27001 and PCI-DSS. The ideal candidate will have 3 years’ experience in a similar Information Security role and have relevant security qualifications - CISM / CISSP or CISA etc. This is a client facing opportunity where you will be expected to travel to customer sites. Reference Number: OG7484 (Application Security, Penetration Testing, Information Security)
- Cloud Network Engineer
- Up to £35,000 Base + Bonus + Possible Share Options
One of our clients, an exciting UK based start-up is on the lookout for a Cloud Network Engineer in Yorkshire. The Cloud Network Engineer will need current CCNA / CCNP level networking experience (Cisco, BGP, IP etc.), cloud networking understanding (Azure, AWS etc.) and current experience ideally within a client facing / consultancy role. (Cloud Engineer, Network Engineer, Azure, AWS, Amazon Web Services) Reference Number: PG7477
- Senior Service Desk Analyst
- Up to £32,000 Base + £6,400 Shift Allowance
We are currently working on behalf of an IT Service Provider based in Wiltshire who are on the lookout for a Senior Service Desk Analyst. The Senior Service Desk Analyst will be responsible for logging, managing and escalating internal & external incidents and requests. This is an excellent opportunity to join a business recognised for what they do and work with a number of top UK businesses. You’ll be able to manage your career development and gain additional training e.g. certifications etc. This role will include a shift (4 days on then 4 days off) which covers 24/7 12 hour shifts The ideal candidate will be currently working in a IT service desk / IT support role ideally in an IT Services business. Reference Number: PG7476 (Service Desk Administrator, Analyst, Support, Service Desk Support, shift work, traning, Information Technology, Customer service, Customer support)
- Data Centre Service Delivery Manager
- Up to £50,000 + Package
A Data Centre Service Delivery Manager is needed to join a specialist connectivity provider in Hertfordshire. The company is going through a huge growth programme and this is an excellent opening for someone to join a business who are working with globally recognised organisations. You’ll be responsible for: Supporting the Commercial Director with management of existing and potential customers being the main point of contact. Maintaining and improving the company’s current and new services Customer relationship management Attending customer meetings in order to provide guidance to customers Keeping up a high quality level of service Updating appropriate documentation such as policy and procedures and making sure these are in place and followed Change and Incident management Service Level Agreements Experience required Must have current experience working in a Data centre environment in a Service Delivery role. An understanding of Data Centre technology and terminology. Experience of dealing with people of all levels within a business (Engineers to Board level) In return you'll have the ability to work in a cutting edge environment and work with a variety of well known international clients REF: PG7475