You may have seen a recent article from the BBC on a security flaw nicknamed "heartbleed" that is leaving many online services vulnerable to attack, and advising that you change all your passwords.
You don't need to change your Warwick account password unless it's the same password that you've used elsewhere on the internet. IT Services have checked Warwick's central IT systems and found them completely unaffected by the bug, so your password will not be vulnerable unless you've used the same one on another site that is affected.
We strongly advise you not to use your University username/email and password as login details for other accounts. This is to limit access to systems and exposure if your University account is compromised. The same applies to any other passwords you have.
For more information on information security, see the Information Security website.