Technical name | Ransom.MSIL.Tear |
---|---|
Classification | Trojan horse |
Type | Ransomware |
Subtype | Cryptovirus |
Point of origin | Istanbul, Turkey |
Author(s) | Utku Sen |
Operating system(s) affected | Microsoft Windows |
Written in | C# |
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]
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]
In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Ideally, only authorized parties can decipher a ciphertext back to plaintext and access the original information. Encryption does not itself prevent interference but denies the intelligible content to a would-be interceptor.
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