Is there any way to force someone to rescan their wallet?

Question

I'm asking in the context of Poloniex having to rescan their wallet conveniently at the time of Monero's all time high in volume, reference:
https://www.reddit.com/r/Monero/comments/4z5sbo/poloniex_running_dry_on_monero_withdrawal/

I'm not accusing Poloniex of anything nefarious, but I just find it interesting that their wallet coincidentally needed to go down for maintenance to rescan when price and volume are at or near all time highs. I'm curious if a determined attacker could induce some kind of corruption in their wallet binary by spamming their wallet with many many small txs with payment ids, or possibly some other way, in order to keep people from depositing more XMR while their pump is ongoing?

Answer 1

Not that I know of, but failed transactions and reorgs can get the wallet's idea of what outputs are spent to get out of sync with the blockchain. This does not require a rescan of the blockchain (just rescan_spent is enough, and it is a lot faster), but it is not widely known, and some people tend to go for the nuclear option first (rescan_spent also did not exist until a few months ago).

This out of sync problem is fixed in the rct branch, too.

Answer 2

No, the disconnected architecture means that the wallet is quite isolated from the Internet-talking daemon.

I have no idea what caused Poloniex to run a rescan, but it is possible for the wallet cache (the .bin file) to be corrupted on disk if simplewallet is interrupted when spooling to disk.