Use for questions about the security of physical locks, as opposed to e.g. write locks on a database.
Questions tagged [locks]
25 questions
157
votes
12 answers
4-dial combination padlock: Is it more secure to zero it out or to blindly spin the dials after locking?
I am partially responsible for some resources protected by a 4-dial combination lock like this one:
There are two things that people will usually do after they've locked it:
reset all the digits to 0, so that the combination reads 0000, or
mash…
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Peter Schilling
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152
votes
3 answers
Does pressing a car remote many times offer denial of service attack for rolling codes?
My understanding of remote car key fobs, and similar security devices with rolling codes, is that the key device is a transmitter that, each time the button is pressed, sends the next secret in a known sequence that is unique to the key. It does not…
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Oddthinking
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120
votes
11 answers
What's to stop someone from 3D print cloning a key?
My friend just posted a picture of her key to instagram and it occurred to me that with such a high res photo, the dimensions of the key could easily be worked out.
Therefore the key could be duplicated.
What's to stop someone malicious from abusing…
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personjerry
- 1,236
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95
votes
3 answers
What is the purpose of the rotating plate in front of the lock?
I am now in Poland and see these everywhere:
The plate can rotate freely,when you insert the key, matching the groove, you rotate the key so it is aligned with the lock and then insert the key.
What is the purpose of this?
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Thomas
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80
votes
6 answers
Can a lock picker slowly undermine the security of a deadbolt door?
I have a space for computers secured with a simple deadbolt. Someone keeps coming to pick the lock. While working there, I have scared them away three times.
There are cameras, but not in useful places or all exits and the building manager won't let…
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Village
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51
votes
1 answer
Vehicle remote key security
How secure are car remote keys? When you lock or unlock your car, can someone spoof or make another remote key?
How do car remote keys work? Do they use some kind of private/public keys, encryption?
Are aftermarket alarm remote keys less secure than…
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Guntis
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23
votes
4 answers
What are the alternatives to door passcodes?
Passwords have been a problem since the dawn of computing. They tend
to be either so complex that no one can remember them, or so obvious
that anyone could guess them.
...
Some users choose to write their passwords down on paper and keep them
…
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storm
- 1,714
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15
votes
3 answers
How many unique house keys can possibly exist?
A Yahoo! answers user suggested that there are 5^5 possible unique configurations for a physical key, but the answer wasn't sourced. I wondered if anyone had similar numbers for how many possible key combinations there are. I ask because, it seems…
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Lou
- 315
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11
votes
1 answer
How do rolling code fobs and receivers synchronise?
This is a follow-up question to my earlier one: Does pressing a car remote many times offer denial of service attack for rolling codes?
I want to emphasize that I am asking this question more to shore up holes in my academic (mis)understanding of…
![](../../users/profiles/40146.webp)
Oddthinking
- 1,767
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- 15
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7
votes
2 answers
Should magnetic locks automatically release in the event of a fire alarm?
Basically what the title says, you'll find many buildings have these types of door locks
which can usually be opened by using a RFID token. While this example photo is glass, lets assume that the door is steel/unbreakable.
In the even of fire what…
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NULLZ
- 11,426
- 17
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6
votes
4 answers
Are keys or RFID tags more secure access control solutions?
Just musing to myself, what is the preferable access control mechanism in high security environments? Locks and Keys or RFID tags?
Going under the assumption that the locks/keys are not knoow to be pickable and that the RFID tags are not currently…
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NULLZ
- 11,426
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3
votes
1 answer
Do dial locks have repeated numbers?
Can dial locks, such as the one below, have repeated numbers in their combination? For example, the combination 10-39-10 has the number 10 repeated twice in it. If so how often is this the case?
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Unknown
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- 5
3
votes
2 answers
Padlocks suitable as teaching aids for public key cryptography - do they exist?
When explaining public key encryption, people commonly use the imagery of keys and padlocks. However, most padlocks have only one key (i.e. only one bitting), and work like this:
The padlock can be locked without any keys; and
The padlock can be…
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sampablokuper
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2
votes
0 answers
Why do car key remotes not use E2EE?
Background
I read an article about how car keys that remotely open one's car are not secure. This answer also talks about different encryption methods being insecure.
The article mentions that common encryption keys were used across many different…
2
votes
1 answer
How vulnerable are rolling codes used in car keyfobs to simple replay attacks?
I've read this question - Vehicle remote key security, and I have a few simpler questions that are not addressed in that one.
I just received a whatsapp viral forward raising a few claims regarding security of car keyfobs. I feel that one or more of…
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Ankush Jain
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