Virus writers have developed malware that can attack the freeware OpenOffice software.

The  macro called Stardust is not considered a threat. It works by attempting to download a porn image from the internet onto a computer and writes some text in a new document.

However, John McCreesh from OpenOffice.org told Computeractive that as the macro does not run automatically, it does not even count as a proof of concept virus.

However it shows that the popular software can be vulnerable to threats in future.

Macro viruses use the programming language built into software such as Microsoft Office. As well as automating common tasks, macros can modify files on a computer and were responsible for several high profile attacks against Microsoft such as Melissa four years ago.

The threat advisory from Kaspersky Labs reports that the macro cannot send itself on to other people because of errors in the code. Although malicious macros are nothing new in themselves, this is first time Kaspersky has found one for OpenOffice

Mr McCreesh went on to say that OpenOffice will always ask for permission before allowing macros in a document to run. There are no changes planned for OpenOffice as a result of this macro as it does not pose any risk to users.