LastPass has noted suspicious activity on its network.
“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.
We are requiring that all users who are logging in from a new device or IP address first verify their account by email, unless you have multifactor authentication enabled. As an added precaution, we will also be prompting users to update their master password.” LastPass
I suggest you do as they instruct:
“If you have a weak master password or if you have reused your master password on any other website, please update it immediately. Then replace the passwords on those other websites.” – ibid
Source:
https://blog.lastpass.com/2015/06/lastpass-security-notice.html/