Threats to instant-messaging systems dropped 33 percent last month, according to Akonix Systems, a supplier of IM security products.
The company tracked 28 new IM threats in August, down from 42 in July. The total in July represented a 24 percent increase from June.
Among the new threats were Pinch, Aolog, Guap, Rbot-AJS and Landis. August also saw the first time in which a virus queried the configuration of the client software to determine the language setting and then send a message in that language.
Kelvir-HI, a variant of the Kelvir virus, can send messages in English, Dutch, French, German, Greek, and Italian, among other languages. The variant represents the increasingly sophisticated social engineering techniques of virus writers, Akonix researchers believe.
"August's Kelvir-HI variant reflects how advanced virus writers are becoming in manipulating IM network settings," Francis Costello, chief technology officer at Akonix, said in a statement.