If you are using the LastPass Password Management service, you may want to go and reset your passwords. They have had a security breach on their network, and although they don’t believe they hackers got into any user accounts, they have confirmed that that LastPass account email addresses, password reminders, server per user salts, and authentication hashes were compromised.
Taken from https://blog.lastpass.com/2015/06/lastpass-security-notice.html/
We want to notify our community that on Friday, our team discovered and blocked suspicious activity on our network. In our investigation, we have found no evidence that encrypted user vault data was taken, nor that LastPass user accounts were accessed. The investigation has shown, however, that LastPass account email addresses, password reminders, server per user salts, and authentication hashes were compromised.
While they have stated that you do not need to change your passwords, this would probably be a prime opportunity to change your passwords anyway if you have not changed them recently.