DSi system flaws

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Revision as of 23:15, 22 August 2021 by PoroCYon (talk | contribs)
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boot0

Summary Description Successful exploitation result Discovered Exploited Discovered by
Undefined instruction/abort exception handler backed by RAM not cleared on reset Much like the 3DS boot0, some of the DSi's exception handlers are backed by RAM which isn't immediately cleared on a reset. Using fault injection, it is possible to cause an undefined instruction exception before the clearing happens, making the CPU jump to code remaining in RAM from the previous boot cycle. This only works on the ARM7, as on the ARM9, it is backed by main memory, which is only initialized by boot1. Code execution under ARM7 boot0 June 2016 Nocash, Normmatt, dark_samus, ApacheThunder (first successful exploit: PoroCYon, March 2021)

boot1

Summary Description Successful exploitation result Fixed in boot1 version Discovered Discovered by
Poor System Menu TMD size check boot1 loads the System Menu's TMD for verification and loading, and it attempts to check the size. However, instead of checking if size > capacity, it checks if size > size, which is always false, resulting in a buffer overflow. Code execution under boot1 Unfixed August 2017 Nocash

System Menu

Summary Description Successful exploitation result Discovered Discovered by
DS games are not patched to verify overlays. While the System Menu checks all cartridge overlays to prevent unauthorized software, no such check exists when the overlays are actually loaded, despite an MIOS-like patcher being possible to implement. By changing the overlay after it is checked, it is possible to run arbitrary code. Code execution under any DS game with overlays. January 2010 Datel, blasty (by reverse engineering Action Replay)