Hardware downgrading firmware & efuses

[eddo12321]

this is half homebrew and half hardware so idk really where to put this
anyway, nintendo made efuses to stop downgrading, but cant you just get a custom firmware that says its the latest and install that? or does that break some fancy signature thing?

 

[Yepi69]

Spoofing and actually being the correct system version is different.
There needs to be an exploit that allows the system to completely skip the eFuse checking part, there's no way to downgrade without skipping eFuse check.

 

[YugamiSekai]

Spoofing and actually being the correct system version is different.
There needs to be an exploit that allows the system to completely skip the eFuse checking part, there's no way to downgrade without skipping eFuse check.

Would that require a kernel, or full on TrustZone exploit?

 

[Loko4]

this is half homebrew and half hardware so idk really where to put this
anyway, nintendo made efuses to stop downgrading, but cant you just get a custom firmware that says its the latest and install that? or does that break some fancy signature thing?

If you already have a custom firmware theres is no point of downgrade.

 

[Yepi69]

Would that require a kernel, or full on TrustZone exploit?

Since its mostly a cold boot process, full exploit.

 

[TheCyberQuake]

You can't just modify firmware and install it as you need the secret keys to sign it for it to pass signature checks. We are very unlikely to ever get those keys. To bypass the signature check, we would need cfw, but if you already have access to cfw you wouldn't need to downgrade anyway

 

[jRRRRRRRRRRR]

According to SwitchBrew (the switch wiki) you can downgrade specific versions to other specific verions like this.

• 2.3 to 2.1, and 2.0.0,

and

• 3.0.2 to 3.0.1

otherwise downgrading isn't possible without a way to bypass efuses.

 

[eddo12321]

Spoofing and actually being the correct system version is different.
There needs to be an exploit that allows the system to completely skip the eFuse checking part, there's no way to downgrade without skipping eFuse check.

Maybe a hardware mod that would make the bootloader not check fuses?

 

[Yepi69]

Maybe a hardware mod that would make the bootloader not check fuses?

ATM, chance is low.
More likely a CFW than a workaround for the eFuses.

 

[Deathscreton]

ATM, chance is low.
More likely a CFW than a workaround for the eFuses.

I could see CFW leading to downgrades as a way of removing eFuse checks though. As for why you'd want to download, more exploits! Downgrade, use eCFW/emuNAND to create a NAND backup and keep yourself safe from future updates. I would prefer to be downgraded as far as possible provided the system can do such a thing.