Yahoo emails

[#1]

Please help!  I have a yahoo email account and I just went in to check it and got a surprise!  Apparently at 14.04pm today I sent 10 emails to various addresses in my contacts including Plusnet, myself and Yahoo! I definately didn't send them! Does anyone have any idea what happened?  The emails are all a bit 'funny' with subjects like nupe, fgpassion, salmaan 21, queen1966. The emails tell the receipient to click on a link and the links are in a foreign language. Does anyone know how/why this happened? Is this some kind of virus? I have McAfee provided by Plusnet and I just did a scan but there's no viruses. What should I do now? Can I prevent it happening in future?

[#2]

Change your yahoo password immediately. I've read reports of other yahoo accounts being hacked before.
Does yahoo not have a list of most recent logons ? Yes it does. You can go into your account settings and view "recent sign in activity" which shows who logged on from which country, when.
Are any in wierd countries?

[#3]

Thanks very much for replying, Kwak.  I did as you suggested and it says  2.04pm, Access type = Yahoo! Mobile (normally when I log on it says Browser), Event = Logged In (that's what it says when I log in too), and Location = ROMANIA!!! (normally it's United Kingdom). I have changed my password. Should I do anything else? I've scanned with McAfee and it says there's no threats etc. Any idea how this person from Romania managed to do this (so that I can prevent it happening again if possible)? It's the same email address/password (which i've now changed too) as my Facebook account. thank you

[#4]

Use a very difficult password to crack - include letters and numbers and make it the maximum length allowed

[#5]

Include one or more non-alphanumeric characters too if you are allowed to do so. The main aim is to make a brute force attack (comparing against a discovered password hash) take too long.

[#6]

Also if at all possible set (or change if there's one set) your security question for password reminders.

[#7]

Thanks everyone

[#8]

You're lucky. Friends of mine have had their Hotmail accounts hacked into and the passwords changed. Total loss...

[#9]

Interesting, if you search for hacked yahoo email a page comes up (wierd name, blind 5 yr old) who was hacked ..
you guessed it, from Romania, and using Yahoo mobile. Makes you wonder WHY yahoo aren't cracking down
if there's some security flaw in mobile logins OR some romanian IP addresses or mobile phones
sitting trying passwords on non Romanian yahoo accounts?
Have you ever used yahoo on your mobile?

[#10]

Hi Kwak, yes I did.  It was about 1 year ago.  I did it about 6 times, and then I tried about another 4 times after that but it wouldn't let me into it (I can't remember what message I got).  Do you think I need to change my mobile number as well?? Things like this are quite frightening because i don;t understand them!

[#11]

Oh I wouldn't change your mobile, probably irrelevant But certainly change password AND as I think suggested, perhaps any security questions, if they able to see how you'd answered.
I just wonder why mobiles seem to be the route to hacking. Maybe yahoo can't block the IP (the computer trying it) so easy.
I don't want to know your old or new password at all but was the old one a simple word like "fluffy" (say a pet name) or "password1" or something? Bad guys can just try the simple common ones on email addresses and hope you see. Or did you use the same password somewhere else?
As I say though makes you wonder why if Romania is the source of these hacks, yahoo don't do something about preventing them.