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Defeating a Laptop's BIOS Password

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Re: Defeating a Laptop's BIOS Password

#81

Post by ineedasername »

Way back in the first years of the 00's, working IT support in college, BIOS passwords were common (though not mandatory) on the Faculty/Staff desktops. So, forgetting passwords was common as well, and at the time we could reset them by opening them up and swapping a jumper to another set of pins. It struck me as fairly useless to have a BIOS password at the time.

Forever after, on bootup, "Warning! Case has been opened!" would flash up on the screen. I assumed that was for warranty purposes, but our IT department was certified for repairs so it didn't really matter.

Re: Defeating a Laptop's BIOS Password

#84

Post by da_chicken »

ineedasername wrote: post #81

Way back in the first years of the 00's, working IT support in college, BIOS passwords were common (though not mandatory) on the Faculty/Staff desktops. So, forgetting passwords was common as well, and at the time we could reset them by opening them up and swapping a jumper to another set of pins. It struck me as fairly useless to have a BIOS password at the time. Forever after, on bootup, "Warning! Case has been ope…

The BIOS should have a reset option for the case open switch. It's just a warning you toggle off in the BIOS. The idea is that only a tech would know the BIOS password to turn it off, so that's how you know that someone knows about it.

It's also unusual that discharging the CMOS removed the boot password. It shouldn't do that. I also worked on similar desktops (they were IBM desktops from before they were spun off) and they didn't have this problem that I can recall. Very few systems had boot passwords, however.

I'm certain that the BIOS passwords didn't clear this way, however, because we had a few systems that had old passwords that nobody knew. Instead, we had a copy of the tech software used to program the BIOS. You had to boot that program and use it to clear the password. HP had a similar program, but that stopped working around 2010 when the computers started to ship with a TPM and you could no longer just clear the content.

Re: Defeating a Laptop's BIOS Password

#85

Post by big_chungus »

sph wrote: post #68

I "cracked" my father's laptop's password when he passed away 15 years ago by buying a similar, broken laptop on eBay for cheap, and unsoldering and switching the ROM/EEPROM containing the BIOS. Probably one of the coolest things I've done as a teenager.

Why re-solder the chip? It seems as though it would be easier to recover data by just yanking the drive, especially since full-disk encryption was quite rare fifteen years ago. Failing that, couldn't you have used a SPI flasher with the existing chip?

Re: Defeating a Laptop's BIOS Password

#86

Post by snazz »

big_chungus wrote: post #85
sph wrote: post #68

I "cracked" my father's laptop's password when he passed away 15 years ago by buying a similar, broken laptop on eBay for cheap, and unsoldering and switching the ROM/EEPROM containing the BIOS. Probably one of the coolest things I've done as a teenager.

Why re-solder the chip? It seems as though it would be easier to recover data by just yanking the drive, especially since full-disk encryption was quite rare fifteen years ago. Failing that, couldn't you have used a SPI flasher with the existing chip?

Some laptop hard drives have a firmware password you have to enter at the BIOS stage to boot it.

Re: Defeating a Laptop's BIOS Password

#87

Post by woodrowbarlow »

Zod666 wrote: post #51
blkhawk wrote: post #34

Earlier quoted context omitted.

There is a guy in hungary that offers unlocking services for about 50EUR. He is a bit difficult to work with (insists on a NDA) but the procedure is as follows: you dump the bios via SPI and send it to him. Afterwards you get a patched image back you flash onto the bios chip. Then you boot and you need to enter some numbers he also sends you (I assume some type of copy protection) and it will unlock and reset the bio…

If you don't mind physically opening the laptop, you open it and take out the CMOS battery, boot it up without it then shut it down and put the CMOS battery back in and boot. The BIOS password will no longer bet set. I don't know if this still works but it used to on older laptops.

i used this method on an old t520 with success.

Re: Defeating a Laptop's BIOS Password

#88

Post by shakna »

da_chicken wrote: post #84
ineedasername wrote: post #81

Way back in the first years of the 00's, working IT support in college, BIOS passwords were common (though not mandatory) on the Faculty/Staff desktops. So, forgetting passwords was common as well, and at the time we could reset them by opening them up and swapping a jumper to another set of pins. It struck me as fairly useless to have a BIOS password at the time. Forever after, on bootup, "Warning! Case has been ope…

The BIOS should have a reset option for the case open switch. It's just a warning you toggle off in the BIOS. The idea is that only a tech would know the BIOS password to turn it off, so that's how you know that someone knows about it. It's also unusual that discharging the CMOS removed the boot password. It shouldn't do that. I also worked on similar desktops (they were IBM desktops from before they were spun off) a…

> It's also unusual that discharging the CMOS removed the boot password. It shouldn't do that.

That's actually the official way to reset the password for a number of systems. [0][1][2]

[0] https://www.dell.com/support/article/au/en/aubsd1/sln170684/...

[1] https://forums.lenovo.com/t5/ThinkStation-Workstations/How-d...

[2] https://h30434.www3.hp.com/t5/Desktop-Boot-and-Lockup/how-to...

Re: Defeating a Laptop's BIOS Password

#89

Post by Galanwe »

jasonhansel wrote: post #73
Galanwe wrote: post #7

Earlier quoted context omitted.

The BIOS does control the boot order sequence for instance. I guess if you have access to it, you could force boot from a malicious USB stick, or the network, that would simulate the disk decryption prompt. I guess you could also remove security measures that your company put in place to e.g. prevent the usage of USB to prevention information leak.

But to do that you could also just (say) clone the disk drive and install the fake prompt on the disk drive itself, right?

Not if secure boot is enabled, your boot loader most likely would not have a trusted signature.

Re: Defeating a Laptop's BIOS Password

#90

Post by pmccarren »

ineedasername wrote: post #81

Way back in the first years of the 00's, working IT support in college, BIOS passwords were common (though not mandatory) on the Faculty/Staff desktops. So, forgetting passwords was common as well, and at the time we could reset them by opening them up and swapping a jumper to another set of pins. It struck me as fairly useless to have a BIOS password at the time. Forever after, on bootup, "Warning! Case has been ope…

Hah, I remember this all too well
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