A Computer Virus which doesn't damage your PC

I am a developer from Italy, and because I usually work with English people, I need to know some new words.

What do you call a 'Computer Virus' which is only annoying but not dangerous?

A benign virus does no harm.

oxforddictionaries.com:

(Of a tumour) not malignant: benign growths

One generic term used for (relatively) nonharmful but unwelcome apps and files that sneak or hitchhike onto a person's computer, often on the coattails of a desired program or download, is potentially unwanted program (PUP). AVG (an antivirus company) describes PUPs this way:

Potentially Unwanted Programs sometimes act very similarly to viruses or spyware. They are usually installed legitimately as a part of another program (often designed as an "AD-Supported program" – in which the End User License Agreement typically prompts the user to accept that, in addition to the desired program, an additional program will also be installed).

Another very common term for unwanted apps or files that may not severely damage, disable, or commandeer one's computer but do compromise system performance in various ways (such as by running activity-monitoring processes in the background, or popping up ads at regular intervals) is malware—a broad category of undesirable software that includes such subcategories as viruses, spyware (monitoring software), and adware (advertisement-serving software).