The move comes after Adobe noticed "significant changes in the threat landscape," said Brad Arkin, director for product security and privacy at the company, on Wednesday.

Adobe plans to issue patches every three months on the second Tuesday of the month, the same day that Microsoft releases its patches, Arkin said. Releasing patches in tandem with Microsoft is easier for administrators, who can test the fixes from both companies at the same time before updating desktop PC images.

Adobe's Reader and Acrobat software are used for creating and reading PDFs (Portable Document Format) files, which is the widely used format for saving Web pages, creating forms and for other uses.

The programs also use JavaScript, a programming language which if not implemented correctly can allow hackers to create PDFs that trigger, for example, a memory corruption problem that can allow for complete control of a computer and all of its data.

Adobe has had a security development lifecycle -- a set of protocols for dealing with problems -- for at least four years. But as Adobe has developed Reader and Acrobat, the company didn't review the old legacy code for security vulnerabilities, Arkin said. It is doing that now.