What is malware XOR obfuscation detection?
XOR obfuscation was used in the corpus to circumvent malware detection and reverse engineering, to hide information that was apparently being exfiltrated, and by malware detection tools for their quarantine directories and to distribute malware signatures.
Is XOR obfuscation technique?
Hussey [22] suggests that XOR is sometimes used as an obfuscation technique to hide data as it is being exfiltrated; we discovered evidence of XOR used for this purpose. Several types of malware have been reported as using simple obfus- cation techniques to hide data being exfiltrated from a victim machine.
What is obfuscation in malware?
Malware obfuscation is a process that makes textual and binary data difficult to understand. Obfuscation techniques are used by attackers to make it difficult for antivirus to detect filterless malware. These techniques to detect novel and known samples of malware in a future dynamic malware detection system.
What is an XOR file?
In cryptography, the simple XOR cipher is a type of additive cipher, an encryption algorithm that operates according to the principles: A 0 = A, A A = 0, A B = B A, (A B) C = A (B C), (B A) A = B 0 = B, where. denotes the exclusive disjunction (XOR) operation.
Which is the most common method of obfuscation in malware?
Let’s see some practical obfuscation examples used in a lot of malware today. The exclusive or operation (represented as XOR) is probably the most commonly used method of obfuscation. This is because it is very easy to implement and easily hides your data from untrained eyes.
How is malware obfuscated by a packer program?
This prevents anybody from viewing the malware’s code until it is placed in memory. This type of obfuscation is achieved using what’s known as a packer program. A packer is piece of software that takes the original malware file and compresses it, thus making all the original code and data unreadable.
Which is an example of the XOR operation?
Let’s try a practical example using the XOR operation. This time we’ll XOR the letter ‘J’ with the letter ‘v’ and observe the results. The first thing we’ll need to do is consult the standard ASCII table and see which numeric value corresponds to these two letters.
How to perform XOR 0x33 against one byte?
It’s a very simple script, and just reads one byte at a time until the end of the file (EOF) is reached, performing an XOR 0x33 against every other byte. Below we have our decrypted file, which I just called ‘decode’.