Hi @stefangroenewald007
If there were any security incidents we would notify all users first via the status page here: https://status.lastpass.com/
Regarding the security of vault data, LastPass operates under a zero-knowledge policy, so the only way to access your data is by using the account password to decrypt the entire vault. Make sure you are not re-using the login password on any other site, and it is of recommended security strength.
Then, I would check the vault and update any weak or reused passwords.