Decrypting Save Data Without The Original 3DS

[Ushimimi]

I have a NN3DSXL running CFW, and I have a very old backup of an SD card from a stock, unmodded 3DS I owned forever ago.
I don't have a NAND dump or movable.sed from the old console, so I assumed I was SOL on restoring the save data from that old SD card backup to my new modded console.

Then, I saw a thread titled "[Question] [3DS] It is possible to decrypt save backups made in system settings?" (I can't post links, since this is a new account), which makes reference to "having a 3DS that has the original 3DS on its friends list", and running homebrew on that 3DS. I do have that, but I can't find any info on what technique that post is referring to or if it's applicable in my case.

Can anyone point me to the discussion that post is alluding to? I've seen a few mentions of it around.

Thanks a lot, and please pray for me...

 

[CoolMe]

and running homebrew on that 3DS.

Your modded n3dsxl you mean, and not your other "unmodded 3ds"?

I do have that,

You mean you have cfw on this modded n3dsxl or..?

 

[Ushimimi]

Sorry, I should rephrase. This entire concept is very big for my very small and smooth brain lmao

The thread I can't link is about recovering save data from an unmodded, raw copy of a 3DS SD card, which is what I have. I do not have the original hardware the save data is from, so I thought I was screwed. That thread makes a reference to a possible technique involving "a 3DS that has the old, missing one on its friends list". I do have a 3DS that has the old, missing 3DS I copied the save data from on its friend list.

The new 3DS with CFW on it is I suppose mostly-irrelevant to the question, since the question is about decrypting the old save data from the old SD card.

 

[CoolMe]

I do have a 3DS that has the old, missing 3DS I copied the save data from on its friend list.

I don't understand what you mean here.
There's only one method to decrypt save but it requires some files which i don't think you have (since that 3ds was unmodded).

 

[Ushimimi]

The thread I am asking about reads:

"If you don't have your movable.sed, then you can still generate it if you have another 3DS that has the Friend code of the broken 3DS in its Friends list."

I was hoping someone could point me to the discussion or post that explains the technique this is referring to.

 

[shadowofdarkness]

You can find out everything with this program. https://github.com/zoogie/seedminer/releases/download/v2.1/RELEASE_v2.1.zip
You'll have to find a system that friended the old system and can run homebrew then get that system to run seedstarter.3dsx and give you the resulting file. Then using info from it and the 32 character folder name from the old 3DS system backed up SD card you can use seedminer to bruteforce a movable.sed that will work enough to decrypt the contents of the SD card backup on a computer using other software like ninfs

The readme.txt in that archive has the instructions. You only need the first couple sections until you have the movable.sed, the last is for hacking a system using it which you don't require.

 

[Ushimimi]

Thank you very much! This is exactly what I was looking for!

Post automatically merged: Apr 24, 2023

Well, here's a conclusion to the story, in case anybody stumbles onto this thread sometime down the line:

I gathered up the id0 from my old SD card. I ran seedstarter, to scrape the movable_part1.sed from a 3DS that had my old one on its friend list. I ran seedminer on my PC for 11 and a half hours, using that data.

No hits. 11 and a half hours, it had processed every possible permutation of the brute force attack. Dead end.

With mounting dread, I scrolled down the friends list and spied another possibility. My ex-boyfriend was on that list as well...and there sure are a lot of pictures of him on this SD card...

I ran seedminer with his movable_part1.sed. In under a second, it was cracked. Frick.

For some reason, I have a backup of my ex-boyfriend's SD card instead of mine. I have been keeping this SD card safe for the better part of a decade, hoping to one day find a way to resurrect the data on it. All along, it was his. Why do I have this? I can't even imagine. It's been polluting my SD card storage for like eight years now without my knowledge.

Anyway, I might release his Pokemon in effigy or something. Get some closure.

Thanks for the help, gang. My data may be gone, but you helped me at least put this to rest!