For security reasons, RSF did not release the identity of the journalist who was taken in for KGB questioning.
Antivirus software flagged suspicious components on the device several days later, prompting them to contact IT specialists at a digital security NGO, which conducted a forensic analysis.
Data recovered indicated that the software was first used on the telephone during the journalist’s interrogation.
Investigators also concluded that ResidentBat was likely to have been used by the Belarusian KGB since at least March 2021 but it was not yet clear who made the software.
President Alexander Lukashenko has ruled Belarus for more than 30 years and crushed all opposition.
According to RSF, independent journalism is “heavily repressed” in Belarus, with journalists facing censorship, intimidation, violence and arbitrary detention.
Around 30 journalists are currently in jail in the country -- one of the highest numbers in the world.
“There seems to be a growing trend in surveillance of civil society,” the RSF report said, calling for an international ban on the technology.
In September, the University of Toronto’s Citizen Lab discovered that FlexiSPY spy software had been installed on the phones of two Kenyan filmmakers after their arrest in May.
In December last year, Amnesty International also accused the Serbian authorities of having installed the NoviSpy spy software on phones used by journalists and activists.
-Agence France-Presse