Phishers are trying to get hold of Yahoo account details by targeting seemingly valueless sections of the site.
Instant messages started to appear this week asking unwitting recipients to check out pictures at an enclosed link. This led to a bogus Yahoo Photos website where users were encouraged to input their account information.
"Yahoo runs a syndicated username and password set-up across its entire online product portfolio. Therefore this attack using Yahoo Photos is designed to steal such information," said a spokesman at internet monitoring firm Websense which identified the scam.
"The Yahoo portfolio includes a number of programmes that require the user to input personal data and, as such, contains broad potential rewards for cyber-criminals."
Websense explained that the details could allow a thief to access and/or change financial and shipping account information for Yahoo's Auctions service.
The Yahoo Small Business service also allows space for small e-commerce sites, increasing the potential rewards for phishers.
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