Its main goal is to fight ransomware by helping victims with free decryption of their files. It is coordinated, among others, by Europol, and it connects law enforcement agencies and private sector companies from around the world. Our main contribution is providing a decryption tool postal 2 awp bitcoin Cryptomix, Cryptfile2 and Cryptoshield ransomware families, which we described some time ago.
The project already helped more than victims and now we can also contribute to this effort. We are proud to take part in this initiative. Sage is postal 2 awp bitcoin new ransomware family, a variant of CryLocker. In this case malspam is the infection vector. Emails from the campaign contain only malicious zip file without any text.
Inside zip attachment there is malicious Word document with macro that downloads and installs ransomware. As we see, there is a lot of fingerprinting and checks, though most of them are quite standard. More interesting features include:.
Someone probably forgot to remove this from the final version, because this is clearly a debugging feature. Before encryption Sage checks for existence of a special debug file:. Of course, not every file is encrypted — only postal 2 awp bitcoin with whitelisted extension are touched:. As usual, this is the most interesting thing in ransomware code.
These values are not arbitrary — this curve postal 2 awp bitcoin also called Curve and is the state of the art in modern cryptography. Curve is used with hardcoded public key for shared secret generation. The exact code looks like this with structures and function names by us:.
This looks like properly implemented Elliptic Curve Diffie-Hellman ECDH protocol, but without private keys saved anywhere they are useful only for decryption and malicious actors can create them anyway using their private key. This postal 2 awp bitcoin look complicated, but almost all those functions are just wrappers for ECC primitive — named CurveEncrypt by us.
For example, computing matching public key is curve secretKey, basePoint — where basePoint is equal to 9 one 9 and 31 zeroes. Shared key computation is postal 2 awp bitcoin similar, but instead of using constant base point we use public key:. What about file encryption? Files are encrypted with ChaCha unconventional algorithm, again and key is appended to output file — but after being encrypted with Curve ChaCha is not very popular algorithm among ransomware creators.
Initially Evil was brought to our attention by an incident reported on By that time the Internet was completely silent on that threat and we had nothing to analyze.
We found first working sample day later, on In this article we will shortly summarize our analysis and conclusions.
Since then, we had relatively high number of infections reported, so we predict that this family of postal 2 awp bitcoin may become a bigger threat in near future. Sure, why complicate things if simple solutions work good enough.
CryptoMix is another ransomware family that is trying to earn money by encrypting victims files and coercing them into paying the ransom. It was observed in the wild being served by the Rig-V exploit kit.
As usual, we discourage anyone from supporting the criminals by paying the ransom. Or any payment portal, for that matter — victim have to write an email and literally wait some time before malware operators kindly send the decryption keys assuming that they will do it, instead of bargaining for even more money.
First of all, using emails for communication with victims is bothersome and need constant attention. Automated portal would be much more reliable and secure for both sides. Content of exchanged emails is very unusual too. Actors claim to be a charity organization! CryptoMix is protected postal 2 awp bitcoin a very primitive packer — the real binary is stored in resources, and xored with a hardcoded postal 2 awp bitcoin.
For some reason, Cuckoo has problems with automatic unpacking of cryptomixer, so we had to write our own unpacker. Using pefile and Yara is very easy:. Before file encryption starts, the ransomware checks internet connectivity using InternetOpenUrl function. Postal 2 awp bitcoin, depending on malware version, either a hardcoded encryption key is used or malware is spinning in an infinite loop until the internet connection is restored.
Most unusual thing here is inclusion of another ransomware extensions for example. UserID given by CryptoMix is not random — it is generated from username and serial number for first disk. Why is this a problem? Due to a cryptographic flaw in encryption, we are able to decrypt CryptoMix and CryptFile2but only sometimes and only if files were encrypted with a vulnerable version.
Detailed research regarding the group have been gathered in the form of report available under the link below. In MarchS21sec published their analysis of the new e-banking trojan horse targetting Polish users. We think in part thanks to the kernelmode. This means that those authors are most certainly fluent in Polish. The e-mail supposedly informed about an undelivered package — however, they also included a link which, after several redirects, lead to the download of a malicious file.
During the summer holidays we observed an increased infection rate of ransomware. We mentioned this type of malware a few times already in the past here is a description of similar malware and here is information detailing how to remove it from your computer. CERT Polska was able to acquire three samples of this malware from three different sources. In every case we were able to determine the infection vector. Most probably, all of the three samples were created by the same group of cybercriminals.
One of the samples came from a hacked. PL, second sample was from a hacked website in. A case of malware on the governmental website was also a subject of our previous blog post. We have recently published postal 2 awp bitcoin article in Polish about ransomware malware mainly WeelsOf spreading in Poland. This kind of ransomware was initally mentioned on the abuse. It demands Euro or PLN in order to unlock our computer.
We also published a UKash code generator that was suppose to fool malware and unlock our computer. Since then, we have encountered versions of this ransomware that simply did not postal 2 awp bitcoin the computer no matter what kind of code was submitted.
Below, we have compiled a few tips, both for advanced users and beginners, on how to remove ransomware, or malware in general. They should work even in cases when the computer will not boot. Introduction Sage is a new ransomware family, a variant of CryLocker. After starting the ransomware, Windows UAC window is shown repeatedly until the user clicks yes. At the end the encryption process is started and all files are encrypted: We can even chat with malware creators: Main function of binary looks like this: More interesting features include: And surely enough, this debug parameter does what it should: Locale Check Sage 2.
This checks user keyboard layouts: Canary file Before encryption Sage checks for existence of a special debug file: Finally, if the file is not found, encryption is initiated.
Extension whitelist Of course, not every file is encrypted — only files with whitelisted extension are touched: Encryption As usual, this is the most interesting thing in ransomware code. The exact code looks like this with structures and function names by us: Shared key computation is very similar, but instead of using constant base point we use public key: Additional postal 2 awp bitcoin Yara rules: Introduction Initially Evil was brought to our attention by postal 2 awp bitcoin incident reported on Campaign CryptoMix is another ransomware family that is trying to earn money by encrypting victims files and coercing them into paying the ransom.
This malware stands out from among others, but not necessarily in a good way. Additionally we have stumbled upon following comment discouraging anyone from paying the ransom: For example, ransom message can look like this most recent variant: Or postal 2 awp bitcoin this older variant: Charity Content of exchanged emails is very unusual too. Using pefile and Yara is very easy: The main function can be expressed as follows: The list of supported extensions constains more than entries: Encryption routine can be summarized with this simplified code: Cryptomix Decryptor Due to a cryptographic flaw in encryption, we are able to decrypt CryptoMix and CryptFile2but only sometimes and only if files were encrypted with a vulnerable version.
Cryptomix payload after unpacking: Banatrix e-banking malware ransomware Postal 2 awp bitcoin To nie Thomas trojan.
How much does it cost exactly using the higher ETH price. However, it is worth keeping your eye on the Lotto to see if Cryptopia works to revive it. First, we need to get Bitcoin pricing data using Quandl s free Bitcoin API. The purpose of these videos are to promote discussion and interest in the crypto-space.