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# Bypassing Anti-Virus by modifying Hex Value

* Download **HxD** to modify the evil file we want.
* **HxD** is a carefully **designed and fast hex editor** which, additionally to raw disk editing and modifying of main memory (RAM), handles files of any size.
* Modifying the hex values, we change the program signature to by bypass the anti-viruses.
* Antivirus use database of signatures to detect malware.

{% embed url="<https://mh-nexus.de/en/hxd/>" %}

* Once its installed run the program and select the evil program.

### Usage

* Rewrite the ascii spaces with random words, be careful to not overwrite the binary.

<figure><img src="/files/2qDLRfAnOEzE5lNyFNU6" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/Bb5xBafJziaTu9Q45vFw" alt=""><figcaption></figcaption></figure>

* Now just save the file and execute it to test it before you deliver it.