EEVblog #762 - How Secure Are Electronic Safe Locks?

  • Published: 06 July 2015
  • How secure are electronic locks used on safes?
    Dave tries a basic first attempt power line analysis attack on a standard La Gard (LG) 3740/3750 Basic electronic digital lock on a CMI home safe.
    Can you crack an electronic digital safe lock with just a resistor and an oscilloscope?
    All sorts of safe cracking techniques are discussed - thermal camera imaging, bumping, drilling, and spiking the solenoid.
    And naturally there is a complete teardown of the La Gard lock and a demonstration on how it works.
    And then Dave does something incredibly dumb, and has to fix it the old fashioned way, Hollywood style.
    It's a tail of epic fails and stunning wins.
    Part 2 is here:


    ST ST62T25 OTP Microcontroller


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Comments • 1 366

  • bob4jjjj
    bob4jjjj  22 hours back

    That was quite a good experiment and very funny when you locked yourself out. First time I have discovered your channel, but I'll be back.

    • H Higgins
      H Higgins  2 days back

      It also has rounded corners to add protection against "peeling" the sides off. Note the difference between this and the other safes you show for comparison.

      • Eddy Bash
        Eddy Bash  3 days back

        Hi !
        I think that a Super long master pin code is present inside the eeprom ! Lol

        Some black boxes exist to open a blocked safe because the owner is dead. ;)

        You should read this eeprom !

        I do love this Big vulnerability!

        • Elvin Haak
          Elvin Haak  6 days back

          Is it really just me that wonderes what happens if you would put100 V AC or DC on that battery-connector ?

          • Eddy Bash
            Eddy Bash  3 days back

            You get locked out ! Lol

        • Thomas Scherrer
          Thomas Scherrer  2 weeks back

          HA HA I was screaming when you realized you locked your self out ha ha what a bummer.. great you did not cut that honost part out, we all do things like that when in a hurry, eager to get moving

          • wiz722
            wiz722  2 weeks back

            Likely, it saves each keypress in RAM along with the timestamp (relative, no need for the actual time, just need the difference between the first pulse and the current one for a duration). So, you press a key. It saves it to memory along with the timestamp. You press another key, and if the key is soon enough after the first press, it saves it, too. This continues until the 6th number. At this point, it compares the codes. Blah, blah, blah. To make every subroutine the same length, you can compare the code every time but send an extra argument if it should be a real comparison (so you don't get locked out every keypress).

            • Goldwing Pilot
              Goldwing Pilot  2 weeks back

              You look like the mechanic in Mad Max and sound like the crocodile hunter Steve Irwin!

              • Locker serving bd Rahmna


                • bull head
                  bull head  4 weeks back


                  • David Leger
                    David Leger  1 months back

                    Did you try a rare earth magnet ??

                    • Gregory Carter
                      Gregory Carter  1 months back

                      Best Laid Plans of Mice and Men - John Steinbeck.

                      • uK8cvPAq
                        uK8cvPAq  2 months back

                        How would someone unlock a safe from the inside? I've got myself into a bit of a pickle.

                        • Gary McKinnon
                          Gary McKinnon  2 months back

                          You can open many of them by throwing them up in the air above a soft surface like a mattress, the motion opens the lock. No logic probes required :)

                          • Richard Samuelson
                            Richard Samuelson  3 months back

                            7:22 Oh, so 'spiking' the safe has nothing to do with alcohol?

                            • diegooo1972
                              diegooo1972  3 months back

                              Still waiting for DaveCad licensing...

                              • BIGS SCORE
                                BIGS SCORE  3 months back

                                Hello everyone , David if you hold a powerful magnet near the solenoid it will unlock (: guaranteed to work just operate the solenoid with Neodymium magnets magnet on from outside the box. you can hear it click. a bit tricky but you have to catch it at the right angle, this is for any digital safe

                                • Ti Network Australia
                                  Ti Network Australia  3 months back

                                  Can you please make couple episodes how to use oscilloscope CRO DSO thank you.

                                  • Justin Jameson
                                    Justin Jameson  4 months back

                                    Coolest video ever, the concept alone is awesome

                                    • Tom Dickinson
                                      Tom Dickinson  4 months back

                                      Far more entertaining then your usual videos, superb

                                      • E H
                                        E H  4 months back

                                        Wwwwwait a minute, ... where 5he hell is my 45 minutes?!

                                        [Edit; you see that above? ... I'm in time-loss shock and it caused a typo. I'm feeling a little woosy. Oh! ... and — If the 2nd video goes into all the detail I expected in this one then double the comedically overdramatic tone you read the remainder in.. hehe.]

                                        I would never spend precious time so frivolously, not for a forty-five minute, choreographed "No." — or a "Nooop!" — maybe be safe and say, "If you want to learn valuable information on the subject matter, then buy a book; if you want to spend near an hour trying to match the content creator's intoxication-adjacent exuberance to all things represented in a heterogeneous sampling of time and atmosphere, well.. don't humiliate yourself; you, like I, will never extract such pure joy and personal reward as our presenter, not even if we spontaneously adapt the ability to asexually reproduce.

                                        I cannot imagine how sky high I would be if I'd actually learned what I assumed was going to be transacted but it's a good thing I'm in bed, prone, because otherwise it would have created obstacles to the screwing I just endured.

                                        In all honesty, my takeaway isn't that bitter.. I was only being dramatic, but I've cereally got to learn how to compulsively parse anything and everything with the option; and I'm being ... super ... cereal.

                                        Hey Mate, soory I didn't catch your name, but your ability to extract happiness from a teasingly long "No." gives me hope I just might be capable of cranking out at least half a smile of wonderment the next time I glance up at the night sky and catch a Milky Way adjacent hypernova spark off. 😁

                                        • thulomanchay
                                          thulomanchay  4 months back

                                          When the spent battery is left inside for too long a time, the connector might corrode, and the circuit corrupted. You'd "lock yourself out".

                                          • 7177
                                            7177  4 months back

                                            Safe saga was riveting indeed. Cheers!

                                            • Happy Days
                                              Happy Days  4 months back

                                              Thanks very interesting. Can confirm the cheap safes are garbage no matter how good the internal electronic controller is just jabbing one of the leds (which protrude through the metal door through holes drlled in) even if you destroy the pcb in the process with a piece of wire bent correctly and knowing where to aim the resistance of the solenoid spring is no more than 10 grams and click turn the handle - safe open. 1 out of 5 stars would not recommend lol.

                                              • J F
                                                J F  5 months back

                                                $800 dollars for a toy. But it complies with industry standards. Please do a video on use emp generator on electronic safes please.

                                                • Паша Коленда
                                                  Паша Коленда  5 months back

                                                  The problem with this one is that lock and solenoid are moving in the same direction and 40kg safe accelerates faster and reaches much higher speed than you were bumbin at. So I don't really think that 800$ is a good price for this one. For 800$ you can make much better one, especially if you are engineer.

                                                  • SqueakyGoose
                                                    SqueakyGoose  5 months back

                                                    have you tried a large earth magnetic? just saw a video on doing that for other safes.

                                                    • James Reedy
                                                      James Reedy  6 months back

                                                      Buddy sent this to me earlier today, apparently someone had success with a S&G digital lock which is very popular brand.

                                                      • Gacheru Mburu
                                                        Gacheru Mburu  6 months back


                                                        • Gacheru Mburu
                                                          Gacheru Mburu  6 months back


                                                          • Simply Doge
                                                            Simply Doge  7 months back

                                                            I like your videos(:

                                                            • alan connelly
                                                              alan connelly  7 months back

                                                              So a hack would be to use the existing bottom holes and back holes to access the selelnoid wires or pull the connecter then weasel in power to the selenoid wires or connecter and Power the selenoid and your "in like flin", heck, may even be able to do this with the provided mounting holes with some creative modified tools and mini camera...

                                                              • Shane Johns
                                                                Shane Johns  8 months back

                                                                If it locks you out for 5-10mins after 4 or so numbers of incorrect combination attempts, then it seems likely that you could easily reset that by simply disconnecting and reconnecting the battery after the lockout. I suppose it could have some kind of capacitor in there that is just there to store enough to keep the 'fault' condition from resetting on battery disconnect.

                                                                • The Eminent Joshua E. Hrouda

                                                                  You could embed a circuit just above the battery compartment, a data logger. Let the rightful owner enter the correct code once or a few times. Then retrieve that data, and manually enter it. Would likely be a bugger to attach. But maybe not.

                                                                  • Simon Arsenault
                                                                    Simon Arsenault  9 months back

                                                                    12:30 FAIL XD

                                                                    • Süleyman Kenar
                                                                      Süleyman Kenar  9 months back

                                                                      "Gravity is a bitch"

                                                                      • Patrick Allen
                                                                        Patrick Allen  9 months back

                                                                        This video has a unique status being both on my Electronics and Funny playlists :D

                                                                        • dickcheney6
                                                                          dickcheney6  10 months back

                                                                          There's also locking mechanisms available that have a redundant mechanical combo lock, as in, either one will open the safe. I like that idea because a keypad is more convenient, but a mechanical lock can easily last 40+ years, and if the keypad breaks, you can get back in without damaging the body or bolts, and just replace the locking mechanism. Dave's situation was the exception, usually if you have to break into your safe, the safe itself is a total loss afterward.

                                                                          • Enpä KerroSitä
                                                                            Enpä KerroSitä  10 months back

                                                                            Holy shit this guy has an annoying voice... but luckily this content is interesting :)

                                                                            • Taunter Atwill
                                                                              Taunter Atwill  10 months back

                                                                              Fuck the electronics. A heavy crowbar with a pipe extension and you pull that box out of the concrete and take it with you without a problem.

                                                                              • mono man
                                                                                mono man  10 months back

                                                                                normally the first wrong digit and the software locks you out like on pin and pay dvd. read the code however.....

                                                                                • Banertd
                                                                                  Banertd  11 months back

                                                                                  1 second to open,using standard CRT TV service tool.

                                                                                  • dat ain't mine
                                                                                    dat ain't mine  11 months back

                                                                                    I think if u connect the doohicky to the thingamabob, it just might work! 🙄

                                                                                    • Robert Chrisman
                                                                                      Robert Chrisman  11 months back

                                                                                      You had me at Bunnings 😂

                                                                                      • kent leonhart
                                                                                        kent leonhart  11 months back

                                                                                        Perfect surgical precision. :P

                                                                                        • Mamo Sargsyan
                                                                                          Mamo Sargsyan  11 months back

                                                                                          you awesome !!!

                                                                                          • Mike Clarke
                                                                                            Mike Clarke  11 months back

                                                                                            I a tech guy, work in technology, I hate these things. I like a good old fashion brinks manual combo lock safe. Have a small old safe from the late 1800's that still works great! so thick heavy (blast proof) no way to break into it easy. Have answer style brinks type about 15 years old. Wanted another so visited several retail places that sell them to check them out, all seem to have a lot of plastic these days, handles are plastic, and some were broken from handling, so that tells me not going to hold up well at all if broken in the store. some used a film type keypad that was worn from people pushing on it, there again not holding up to daily use if numbers are worn off useless. And then one would not work, store employee was going to change the batteries, opened up and was all corroded inside, never got to see it operate. Then I decided, not having one. but can't find anything without the damn electronic POS locks on them now.

                                                                                            • Maxwell mc
                                                                                              Maxwell mc  11 months back

                                                                                              Funny dude .

                                                                                              • Robert Allgood
                                                                                                Robert Allgood  11 months back

                                                                                                if you can get to the solenoid wires apply a 9 V battery across the wires an bingo your in! 2 pinchers to break through insulation. one on each.