Usually you will receive communications from these yahoo spammers and hackers addressed to your spam section though some of them go to your mail box.
When you open your email in your yahoo mail box immediately investigate it. Look for the sender and the addressee. The heading of the email will tell you who is the sender with the word “from” and the addressee with the word “to”.
Yahoo spammers and hackers are using “Yahoo! Member Services “. Beware with these senders. They are not employees of yahoo. The yahoo member services employees will never send you email without using your yahoo email valid address.
Their email will look like this:
From: Yahoo! Member Services
To: (The sender did not write my yahoo email valid address here)
For Security Precaution and for optimal viewing of the Yahoo Web site, we recommend that you enable CSS.
For your security, we are currently updating our services. So you are required to log on to your Online Yahoo Account with the provided link below. For immediate access, please Sign on to verify your identity: Click Here
Thank you for helping us serve you better. Copyright © 2011 Yahoo! Inc. All rights reserved.
If you clicked the link they provided to you - you will be redirected to sign in section. And when you log in on that section your yahoo ID and other identities are automatically hacked.