“Tinba” or “Zusy” was discovered in 2012 and infected tens of thousands of computers in Turkey. It is notable for having a very small code base — just 20K — but capabilities similar to malware larger in size. Tinba can interfere with online banking sessions, creating new fields that users must fill out during an online banking session. The leak of its source code means other cybercriminals could begin using it, as such programs are often only offered for sale in forums.”]
Source: https://www.computerworld.com/article/2489867/source-code-for-tiny–tinba–banking-malware-leaked.html