Do note, I have done this 2 times and have never had an issue!
Why?
I have heard that some users of steemconnect have had their tokens stolen from utopian-io, meaning hackers can use these to cast votes, author posts and comments and broadcast custom_json as if it had come from your account.
Now, resetting keys over this may be a little overkill, but since I imagine your steemit account is precious to you, I don't think it would be a bad idea, you can't ever be too safe, can you?
Getting on with it
Now, here comes a link to steemit, but since there are so many scams around, I will also tell you how to access it on https://steemit.com, it is available here: https://steemit.com/change_password, but as I said, since so many fakes are going around, you can go to steemit, click this menu icon:
And then this item:
Then, you can click it and you will be presented with a page like this:
Enter your account name, your current master key/password and then click Click to generate password to generate a new one, now store this new password, and make sure it is correct, into a password manager or other secure location where you keep your steemit keys!
Now, enter/paste it into the second box, check both checkboxes and submit the form, your password will now change, but steemit MAY say that it is invalid for ~1 Minute before accepting the new password, so don't panic like I did, and anyway, if it really does go bad, you can go back to the menu and click Recover a stolen account and provide your old account password (you may have to provide additional info to recover it but considering your the owner, you should know your account pretty well).
What, where is my active, posting and memo key?
You will have to go to your wallet on steemit.com and click permissions, in this tab, you will be able to reveal your posting and memo key instantly, and you can find out your active key by re-entering your memo key.
Hope you found this useful!

About CADawg:
CADawg is Brittish, 16 Years old and wants to become a web developer/programmer.
He currently knows 7 Programming Languages: Visual Basic, Python 2, PHP, HTML, (S)CSS, JavaScript and C++
He wishes to pay for his driving lessons using his earnings from steemit.
He dreams to start his own web development/programming business and travel around the world, exploring all different cultures. CADawg enjoys writing code, mainly in PHP and Python in his free time, as well as playing games.
And Vote For SteemGigs as Witness or Click Here and enter steemgigs in the box, or if you want to give him your voting power and decisions, on that same page type in surpassinggoogle in the second box as a proxy.
Support his other brainchild projects like #untalented, #steemgigs and #teardrops.
Thank you!
Do note, I have done this 2 times and have never had an issue!