Hidden Tear is the first open-source ransomware trojan that targets computers running Microsoft Windows[1] The original sample was posted in August 2015 to GitHub.[2]

Hidden Tear
Technical nameRansom.MSIL.Tear
ClassificationTrojan horse
Point of originIstanbul, Turkey
Author(s)Utku Sen
Operating system(s) affectedMicrosoft Windows
Written inC#

When Hidden Tear is activated, it encrypts certain types of files using a symmetric AES algorithm, then sends the symmetric key to the malware's control servers.[3] However, as Utku Sen claimed "All my malware codes are backdoored on purpose", Hidden Tear has an encryption backdoor, thus allowing him to crack various samples.[4]


  1. ^ Pauli, Darren. "Ransomware blueprints published on GitHub in the name of education". The Register.
  2. ^ Paganini, Pierluigi (18 August 2015). "Hidden Tear Ransomware is now open Source and available on GitHub". Security Affairs.
  3. ^ Balaban, David (20 March 2016). "Hidden Tear Project: Forbidden Fruit Is the Sweetest | The State of Security". The State of Security.
  4. ^ Kovacs, Eduard. "Encryption Flaw Used to Crack Cryptear Ransomware | SecurityWeek.Com". Security Week.