iPhone Removing jailbreak and malware with DFU restore

[Didith194325]

According to Apple's iOS security documents, the secure boot chain utilized by iOS on bootup is the following:

BootROM verifies Low Level Bootloader; if failed, device enters DFU mode

LLB verifies iBoot, which verifies the kernel; if failed, device enters recovery mode

If I restore my iPhone from iTunes by manually entering DFU mode, will all system software be erased from the LLB upward and replaced with the newest iOS? If not, I am concerned that malware could reside in the bootloader(s) and remain with my device after the reset. Because I jailbroke my device back in iOS 8.1, I haven't updated it since and I thereby have been vulnerable to browser exploits, etc. I have not exercised good usage practices with web browsing, so I assume my phone has been compromised.

 

[NougatDude]

According to Apple's iOS security documents, the secure boot chain utilized by iOS on bootup is the following:

BootROM verifies Low Level Bootloader; if failed, device enters DFU mode

LLB verifies iBoot, which verifies the kernel; if failed, device enters recovery mode

If I restore my iPhone from iTunes by manually entering DFU mode, will all system software be erased from the LLB upward and replaced with the newest iOS? If not, I am concerned that malware could reside in the bootloader(s) and remain with my device after the reset. Because I jailbroke my device back in iOS 8.1, I haven't updated it since and I thereby have been vulnerable to browser exploits, etc. I have not exercised good usage practices with web browsing, so I assume my phone has been compromised.

Bleach that iPhone asap and use throw away phones now on

 

[eyoungren]

According to Apple's iOS security documents, the secure boot chain utilized by iOS on bootup is the following:

BootROM verifies Low Level Bootloader; if failed, device enters DFU mode

LLB verifies iBoot, which verifies the kernel; if failed, device enters recovery mode

If I restore my iPhone from iTunes by manually entering DFU mode, will all system software be erased from the LLB upward and replaced with the newest iOS? If not, I am concerned that malware could reside in the bootloader(s) and remain with my device after the reset. Because I jailbroke my device back in iOS 8.1, I haven't updated it since and I thereby have been vulnerable to browser exploits, etc. I have not exercised good usage practices with web browsing, so I assume my phone has been compromised.

There hasn't been a known bootrom exploit (hack) since the iPhone 4. It's the one reason no one can downgrade or jailbreak with impunity. There's always been a catch or workaround for certain devices that does not involve a bootrom exploit.

Unless your life situation is such that world governments consider you a dangerous threat, your chances of being infected by a malicious bootrom exploit are so near zero it probably doesn't even register.

Wipe your phone with DFU mode and don't worry about it. Using DFU wipes all traces of a jailbreak.

 

[Didith194325]

There hasn't been a known bootrom exploit (hack) since the iPhone 4. It's the one reason no one can downgrade or jailbreak with impunity. There's always been a catch or workaround for certain devices that does not involve a bootrom exploit.

Unless your life situation is such that world governments consider you a dangerous threat, your chances of being infected by a malicious bootrom exploit are so near zero it probably doesn't even register.

Wipe your phone with DFU mode and don't worry about it. Using DFU wipes all traces of a jailbreak.

I am aware that the bootrom has not had a known exploit for a number of years. But at what level does DFU mode restore the software to factory defaults? Does it completely wipe the bootloaders (LLB, iBoot, and up), thereby annihilating all traces of the previous operating system save the hardwired bootrom, or does it retain pieces of the firmware to facilitate the new install?

 

[Applejuiced]

There hasn't been a known bootrom exploit (hack) since the iPhone 4. It's the one reason no one can downgrade or jailbreak with impunity. There's always been a catch or workaround for certain devices that does not involve a bootrom exploit.

Unless your life situation is such that world governments consider you a dangerous threat, your chances of being infected by a malicious bootrom exploit are so near zero it probably doesn't even register.

Wipe your phone with DFU mode and don't worry about it. Using DFU wipes all traces of a jailbreak.

I dearly miss the Limera1n iboot exploit
Those were the good old times...