Decryptor for Wanacry Ransomware

WannaCry

A ransomware that is exploiting “ETERNALBLUE” a vulnerability found in the NSA exploits released by the ShadowBrokers.
The WannaCry ransomware attack was a worldwide cyberattack by the WannaCry ransomware cryptoworm, which targeted computers running the Microsoft Windows operating system by encrypting data and demanding ransom payments in the Bitcoin cryptocurrency.

wanakiwi is based on wanadecrypt which makes possible for lucky users to :

Recover the private user key in memory to save it as 00000000.dky
Decrypt all of their files
The primes extraction method is based on Adrien Guinet’s [wannakey] (https://github.com/aguinet/wannakey) which consist of scanning the WannaCry process memory to recover the prime numbers that were not cleaned during CryptReleaseContext().

Usage

wanakiwi.exe [PID]
PID is an optional parameter, by default the utility will look for any of this process:
wnry.exe
wcry.exe
data_1.exe
ed01ebfbc9eb5bbea545af4d01bf5f1071661840480439c6e5babe8e080e41aa.exe

 

Limitations

Given the fact this method relies on scanning the address space of the process that generated those keys, this means that if this process had been killed by, for instance, a reboot – the original process memory will be lost. It is very important for users to NOT reboot their system before trying this tool.
Secondly, because of the same reason, we do not know how long the prime numbers will be kept in the address space before being reused by the process. This is why it is important to try this utility ASAP.

This is not a perfect tool, but this has been so far the best solution for victims who had no backup.

Compatibility only 32 Bit

Windows XP
Windows 2003
Windows 7

Does it modify the original encrypted files?

No, the original encrypted files (.WNCRY) remain unmodified. The decrypted files are generated as separate files.=

Vinesh Redkar
Vinesh Redkar
Senior Security Researcher

Security professional with over 9 years of experience in the security domain across various industries such as Finance, Insurance, Telecom, and government