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Other processes that the user initiates then inherit this token. In other cases, lsass. Read also the 6. 36 reviews. When it is infected it doesn't run neither regedit. No need for panic but keep your eyes open. Virus removal information can help determining whether you're dealing wtih fake lsass. Lord. Scav PC shuts down the system with code 1. See also: Link. Mark It is required for Win. XP to work. Viruses (Sasser) attack it! Joe If you have the Sasser worm: abort shutdown by going to run and enter cmd, then type shutdown - a, make sure you update windows entirely See also: Linkthanks Computer reboots at random, patch helped immediately Robert When I'm connected to the net. Whenever I enter to the net it infecting in 2. I cleaned it very difficult by updating windows security and using special cleaners for this virus. Mehmet Ali ALTAN Lsass. Sawyer its either the sasser worm or its not the problem Jo. Se An. Dr. Es Mc. Afee says nothing about this virus creating any file named lsass. It does say that the virus causes the computer to reboot by crashing the lsass. Subsequent error messages mention this legitimate process as having failed. There is NO need to remove lsass. This file is not reliable. Read a complete Kaspersky Antivirus 2017 review. Find which are the pros and cons of Kaspersky Antivirus before decide to install and test it. Microsoft Office is the undisputedly reliable software that provides technologically reliant publishing programs. These include Microsoft PowerPoint, Access, Excel. Lyberty.com's weekly/monthly splash page. Farid sabotages Messenger restart in 6. Matt Error messages containing lsass. Sasser- worm. Cruel Device As has been said, the worm exploits a bug in lsass. Lsass. exe is NOT the worm itself. If it were a worm, it certainly wouldn't be advertising itself by displaying a message with its own name in it. Troy This is not a virus, the Sasser worm attacks the lsass process and that is why your computer may shutdown, since the worm stops the lsass process from working Samantha Lsass. Isass. exe (isass) is not the same but looks like same.. I was infected by this 3. Bob The Windows File itself isn't dangerous, what everyone here is describing is a virus that fakes the windows filename - so lets not get paranoid about every lsass. Martyn Just use Windows Explorer to check the date of the file against other files in c: \windows\System. If you find lots of files with the same date it usually means it's a required Windows file. Another way to check files is to do a right- click on their name then select Properties and look at the various info listed there. Helvetica i have done research on this program and i think people are getting confused with sasser virus this lsass is a system program if you remove it your computer is left wide open for an attacker as lsass. Anywhere else and it's a virus! Caution, Blueyonder will tell you to search for sasser files and if you find lsass. It looks like its gone when it has not. Jon Sasser victim A default startup process which controls log on security. The following link provides a list of default startup processes for W2. K. Winlogon will then react on whether the user is properly authed or not. Die, Die Salomon PC shuts down the system with code 1. John It causes your machine to reboot over and over Addy Authentication service located in various places, but should only run out of c: \winnt\system. Other seemingly safe locations are C: \winnt$Nt. Service. Pack. Uninstall$, c: \winnt\$Nt. Uninstall*, c: \winnt\Service. Pack. Files\i. 38. Brian. G Windows critical updates include this file. It is imperitive that you have the latest updates to be protected from viruses/worms/trojans Doug It's just the same name as the Sasser virus, but it is a f*cking Windows Process See also: Link. Dj Project Ho This is due to the sasser virus (and variations) attacking the whole system 3. It will cause your computer to shutdown in approximately 6. In the code: the time to shut down - 6. Whenever you access the internet certain sites (with http) activate it; then you have the allocated time to shutdown. Other variations include shutdown times of 3. The worm is rapidly transmitted over a LAN and replicates instantly. However, the good news is: it is nothing that antivirus doesn't handle. No problems with restarting or otherwise.. Always reboots my computer before the system updates have a change to download! It's a totally new comp too, so I don't see how it could be a virus. Update Windows often to prevent problems. Kachiko When i seeee (YOUR COMPUTER WILL BE SHUTDOWN AFTER 6. SEC) simply go to ms dos and type . Naseer It causes many unvolentary shutdowns, shame on MS? Jarmo Its just a normal OS file. If you have problems with your computer shutting you down saying there was an error with it.. Then you should look into the sasser virus. Once you update to the windows xp service packet 2 you will have the lsass. All three in windows one in the service packet folder one in the system. Software. Distribution. If the file is in any or all of these directories it is fine. Solace Real windows file (unless tampered with). Love reading others lack of knowledge here on the subject. Poindexter i know that i had service pack 2 for xp and when i removed it back to the previous service pack 1, it gave me lsass. Seems to keep my hard drive busy Lloyd Plueschow This file compels the PC to reboot showing one minute alert message. Aatif Ijaz It reboots your system at any time jami i've deleted 6 of the same virus in last few hours called W3. HLLW. Gaobot. gen with filename lsass. Travis This is not a harmful process Prashan it works depends and shut down the system at random Anup Deb Isass. After that, it will give you a warning window, that the computer will shut down after . If you have the proces starting with i - - that's the worm. If you have proces starting with l - - that's windows file for logon : ) Anyone who thinks this is . This is a core security authentication file. Anyone who marked this dangerous is confusing it with . A S Windows Operating System File, Service Authentication. If not in system. But it sure seems like it's taking up alot of processor power. Also svchost seems to be running quite high Charlie There is very important that you see in Windows Task Manager\processes is it lsass. Lsasss. exe is Saser virus! I have no idea how to correct this problem Jana Legitimate XP file, is targeted by viruses, is NOT a worm/spyware. Infection of this file is due to negligance of user. The Sasser Worm is the most common problem associated with it. The Sasser Worm attacks the file, and as a safety precaution, Windows shuts down so it can restart a fresh copy of the file. The problem is not normally with the file itself. Updating Windows will fix this problem. Service packet 2 lololol! Lou. Daman This file has a lot of flaws which viruses target ie sasser virus. If attacked you will have problems that even windows updates won't clear. Your better off either going into safe mode to run your antivirus then or reformatting Al Hession The process by itself is not dangerous, but it is easily infected by virus sasser, who has harmful effects. Vernieri (Argentina) Something to do with windows authentication. When LSASS. exe is corrupted by Sasser or one of its variants, it causes Windows to reboot. From what I understand, anything that causes LSASS to operate improperly will cause the NT Authority Service to reboot the computer. You stop the reboot process by typing . Open the internet, then an error box from Microsoft appear(send the prob. A timer is lauch at this moment and you have 1 minute to find something. Not dangerous but very bored! Bob The lsass. exe file is needed for logon authentication and is needed especially in a client/server environment. Turn your Arduino UNO into a USB HID keyboard, and make buttons that do whatever you want. Make it a useful tool, with new buttons for Cut/Copy/Paste or Volume+. ![]()
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The code can easily be changed to make the buttons perform other actions, by consulting the mapping tables in the USB HID documentation. Hacking the PIC 1. F1. 32. 0 « bunnie's blog. I thought it would be fun to try out some of the hacking techniques I had heard about on the PIC series of microcontrollers. PIC microcontrollers typically come with a set of “configuration fuses” that typically include settings to prevent the modification or readback of certain regions of memory. Quite often, a legitimate need arises to read out the contents of a secured, programmed PIC. A typical example is a company that has lost the documentation or the personnel that originally created the codes for a secured PIC. This often happens when a company needs to revise or upgrade a legacy line of products. I scored four PIC1. F1. 32. 0’s from Joe’s stash (it’s nice having lots of fellow hackers in San Diego) and started stripping them down. This is what a PIC1. F1. 32. 0 looks like in its native state: The first thing to do is to take the top off so you can see the silicon within. While there are many homebrew techniques for doing this, they typically involve the application of fuming Nitric or Sulfuric acid. Neither of these are compounds that you would want to have around your home, nor are they easy to obtain since Nitric acid in particular is an important compound for explosives fabrication. I’ve found that the easiest and most reliable way to do this is to just send the part to a failure analysis lab, such as MEFAS, and for about $5. For this project, I decapped three total parts; two were functionally decapped (silicon revealed with device still in lead frame, fully functional), and the last one was fully decapsulated so that it was just a bare silicon die completely absent a package. The last die was fully decapsulated because my inspection microscope has a very short working distance at the highest magnifications. A little sweeping around the die revealed several prominent features, as shown below: The above annotations are my best guesses at what various structures do; I could be wrong, and if you happen to have anything to share, please do post a note! One set of structures grabbed my attention immediately: a set of metal shields over transistors, following a regular pattern that had about the right number of devices to account for all the security bits. Full metal shields covering a device is very rare in silicon, and like a big X marking the spot, it draws attention to itself as holding something very important. Let’s think a little bit more about this metal shield. What is the significance? First, let’s review some interesting facts about FLASH technology (the type of memory technology used in this PIC device to store the security fuse information). FLASH technology uses a floating- gate transistor structure very similar to that found in the old UV- eraseable EPROM technologies (remember the days of the ceramic packaged 2. Data is stored in both FLASH and UV- EPROM devices by causing electrons to tunnel into the floating gate, where the electrons will remain for decades. The extra electrons residing in the floating gate creates a measurable offset in the characteristics of the storage transistor. The difference is that FLASH memory can withdraw the stored electrons (erase the device) using only electrical pulses, whereas a UV- EPROM requires energetic photons to knock the electrons out of the floating gate. The UV light required to accomplish this is typically on a wavelength of around 2. This wavelength of UV is a bit difficult to manipulate, since it requires expensive quartz optics to manipulate without excessive loss. Here’s the important observation that comes out of these facts: FLASH devices can usually also be erased using UV light since they have a similar transistor structure to UV- EPROM devices. The encapsulation around a FLASH device normally prevents any UV light from effectively reaching the die, but since the PIC devices had the plastic around them removed, I can now attempt to apply UV light to see what happens. I performed a simple experiment where I programmed the PIC device with a ramping pattern (0x. FF over and over again) and then tossed it in my UV- EPROM eraser for the length of oh, about a good long shower and some email checking. When I took the device out of the eraser, I found that indeed the FLASH memory was blanked to it’s normal all 1’s state, and that the security fuses were unaffected. Significantly, if I did not bake the PIC device for long enough, I would get odd readings out of the array, such as all 0’s, a phenomemon that I do not understand. I’m supposing it could be due to some effect involving incomplete erasure and the reference bitlines used to drive the reference leg of the sense amps on the FLASH array. Also note that the UV light works just as well on the EEPROM array. Clearly, the metal shields over the security fuses were provisioned to thwart attempts to selectively erase the security fuses while leaving the FLASH memory array unaffected. The picture above illustrates the problem I have (and its solution) (click on the image for a larger, clearer version). In order for the FLASH memory transistor to be erased, high- intensity UV light must strike the floating gate. The metal shield effectively reflects all of the incident light. However, due to the optical index mismatch between the oxide and the silicon interfaces, light at certain angles will reflect off of the silicon surface. In order to witness an example of this reflective effect, jump in a swimming pool and submerse your head and look up at the water- air interface. You will note that the water looks highly reflective at an oblique angle. This is due to the index mismatch between water and air causing total internal reflection of light. This reflection can be used to cause the UV light to bounce up and the metal shield, and bounce back onto the floating gate. Thus, by angling the PIC inside the ROM eraser, I can get enough light to bounce into the FLASH memory transistor region and cause erasure. After a couple of attempts, I developed a technique that seems to work relatively well. Picture of the chip inside the UV eraser (note blue halo around chip due to active UV lamp). The chip is stuck into the antistatic foam at an angle. This still doesn’t prevent me from erasing the desired data in the program FLASH space. In order to prevent erasure of this data, a hard- mask is formed using a very carefully cut piece of electrical tape that was stuck onto the surface of the die using a steady hand, two tweezers, and a microscope. The electrical tape effectively blocks the UV light from directly hitting the FLASH code memory regions, and it also somewhat absorbs light bounced back from the silicon substrate. Here’s a picture of the die in package with electrical tape over the FLASH rom array. Using this technique, I was able to effectively reset the security fuses without impacting the FLASH code array too much. The pictures below show the array memory status according to the programming/readback tool I was using. A part of the code array was still erased, but probably some judicious resizing of the electrical tape could fix that problem. Screenshot of PIC programmer workspace of device settings before erasure. Note settings of security fuses and the values programmed in the FLASH rom in the window behind the fuse window. Screenshot of PIC programmer workspace of device settings after erasure. Note that security fuses are disabled while the FLASH rom contens in the window behind the fuse window read out identically to what was programmed in previously. And thus one can selective erase portions of a PIC’s contents. |
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