Making a resurgence among malware writers is steganography, which means to hide in plain sight, according to Dell Security’s Cyber Threats Unit.
The Stegoloader malware family, also known as Win32/Gatak.DR (Microsoft) and TSPY_GATAK.GTK (Trend Micro), appears to target healthcare, education, and manufacturing, and it does so with a seemingly innocent Portable Network Graphics (PNG) picture of the Earth in space.
Steganography, which combines the Greek words for “covered, concealed, or protected” with “writing,” was first coined around 1499 in a book, Steganographia, by Johannes Trithemius.