Big permalink problem due to hacked site.

A spammer ran some script across my site, and I don’t know exactly what it did. But I do know it has completely messed up the permalinks, in a way I’ve never seen before.

I upgraded to the latest version, but still this didn’t fix the problem. The issue is, even if I attempt to update the permalink options from the Settings menu, I just get a blank page. This also happens if I attempt to post etc… This means the permalink structure is ‘stuck’ on /%postname%/ (custom) – If I attempt to put it back to the original (month & name) and then press ‘Save changes’, I get a blank page.

Can I override in the DB to set it to month & name, and then manually paste in the .htaccess month & name code? If so, what is the option in the DB, and is anyone able to post a vanilla month & name .htaccess code block?

Has anyone seen this happen before? This is driving me nuts!

thanks!