The Mozilla Corporation has criticised Apple over its methods for spreading the Safari web browser.

Mozilla chief executive John Lilly said in a blog posting that Apple's decision to offer Safari to Windows users through its Software Update utility violates user trust and could hamper security efforts.

Lilly claimed that tools such as Software Update are traditionally used only to distribute patches and updates for already installed applications, and that offering the browser to users that do not already have it is a misuse of the service.

"What Apple is doing now with its Apple Software Update on Windows is wrong, " wrote Lilly.

"It undermines the trust relationship great companies have with their customers, and that is bad not just for Apple but for the security of the whole web."

Lilly is concerned that if users lose their trust in Software Update, future security patches may be ignored and users will be left exposed to attack.

"There is an implicit trust between software makers and customers in this regard. As a software maker we promise to do our very best to keep users safe and will provide the quickest updates possible, with absolutely no other agenda, " he wrote.

"And when the user trusts the software maker, they will generally go ahead and install the patch, keeping themselves and everyone else safe."