The tools have legitimate purposes for fighting cybercrime, but when used by authoritarian regimes "can be turned into formidable censorship and surveillance weapons against human rights defenders and independent news providers."
"The lack of legislation and oversight of trade in these 'digital weapons' allows authoritarian governments to identify critical journalists and citizen journalists and go after them," RSF said.
RSF has published an "online survival kit" with tools and tips for activists and journalists to better safeguard their privacy.
Even RSF itself has proved a target. In January, the group's website was hacked and rigged to attack the computers of people visiting the site. Hackers often target websites that attract a particular type of visitor.
Send news tips and comments to email@example.com. Follow me on Twitter: @jeremy_kirk