Kek. Yeah, shit was really unstable back then. At this point, the 3ds has mostly passed the stage where malware can have a big impact, I feel, since restoring your nand is simple as long as you have the backup.
It's actually kinda strange, really, the lack of malware for 3ds. Vita has some, the DS had some, I'm sure there's been some for other consoles, but not really anything for 3ds.