09:35 11th February 2009
Web users should avoid accessing sensitive accounts on public computers as they could lack the most basic security systems, according to Sophos.
The company, which provides protection for business networks, said that people should avoid doing online banking on public computers and should even reconsider whether they are willing to risk logging onto their email account.
Graham Cluley, senior technology consultant at the firm, said that there was no knowing how secure a public computer was or whether a previous user may have installed some kind of malicious software.
Mr Cluley said: "You shouldn't be logging into your email and things like that because you cannot be confident as to the security of that computer."
He added that dictionary words should be avoided when choosing a password in order to improve security levels.
Web users could pursue programming courses and IT training to enhance their understanding of internet security.
Social messaging service Twitter was recently attacked by a hacker, prompting calls from Sophos to strengthen password security.
