# T1027.002 - Software Packing
## [Description from ATT&CK](https://attack.mitre.org/techniques/T1027/002)
<blockquote>Adversaries may perform software packing or virtual machine software protection to conceal their code. Software packing is a method of compressing or encrypting an executable. Packing an executable changes the file signature in an attempt to avoid signature-based detection. Most decompression techniques decompress the executable code in memory. Virtual machine software protection translates an executable's original code into a special format that only a special virtual machine can run. A virtual machine is then called to run this code.(Citation: ESET FinFisher Jan 2018) 

Utilities used to perform software packing are called packers. Example packers are MPRESS and UPX. A more comprehensive list of known packers is available, (Citation: Wikipedia Exe Compression) but adversaries may create their own packing techniques that do not leave the same artifacts as well-known packers to evade defenses.  </blockquote>

## Atomic Tests

- [Atomic Test #1 - Binary simply packed by UPX (linux)](#atomic-test-1---binary-simply-packed-by-upx-linux)

- [Atomic Test #2 - Binary packed by UPX, with modified headers (linux)](#atomic-test-2---binary-packed-by-upx-with-modified-headers-linux)

- [Atomic Test #3 - Binary simply packed by UPX](#atomic-test-3---binary-simply-packed-by-upx)

- [Atomic Test #4 - Binary packed by UPX, with modified headers](#atomic-test-4---binary-packed-by-upx-with-modified-headers)


<br/>

## Atomic Test #1 - Binary simply packed by UPX (linux)
Copies and then runs a simple binary (just outputting "the cake is a lie"), that was packed by UPX.
No other protection/compression were applied.

**Supported Platforms:** Linux


**auto_generated_guid:** 11c46cd8-e471-450e-acb8-52a1216ae6a4





#### Inputs:
| Name | Description | Type | Default Value |
|------|-------------|------|---------------|
| bin_path | Packed binary | Path | PathToAtomicsFolder/T1027.002/bin/linux/test_upx|


#### Attack Commands: Run with `sh`! 


```sh
cp #{bin_path} /tmp/packed_bin && /tmp/packed_bin
```

#### Cleanup Commands:
```sh
rm /tmp/packed_bin
```





<br/>
<br/>

## Atomic Test #2 - Binary packed by UPX, with modified headers (linux)
Copies and then runs a simple binary (just outputting "the cake is a lie"), that was packed by UPX.

The UPX magic number (`0x55505821`, "`UPX!`") was changed to (`0x4c4f5452`, "`LOTR`"). This prevents the binary from being detected
by some methods, and especially UPX is not able to uncompress it any more.

**Supported Platforms:** Linux


**auto_generated_guid:** f06197f8-ff46-48c2-a0c6-afc1b50665e1





#### Inputs:
| Name | Description | Type | Default Value |
|------|-------------|------|---------------|
| bin_path | Packed binary | Path | PathToAtomicsFolder/T1027.002/bin/linux/test_upx_header_changed|


#### Attack Commands: Run with `sh`! 


```sh
cp #{bin_path} /tmp/packed_bin && /tmp/packed_bin
```

#### Cleanup Commands:
```sh
rm /tmp/packed_bin
```





<br/>
<br/>

## Atomic Test #3 - Binary simply packed by UPX
Copies and then runs a simple binary (just outputting "the cake is a lie"), that was packed by UPX.
No other protection/compression were applied.

**Supported Platforms:** macOS


**auto_generated_guid:** b16ef901-00bb-4dda-b4fc-a04db5067e20





#### Inputs:
| Name | Description | Type | Default Value |
|------|-------------|------|---------------|
| bin_path | Packed binary | Path | PathToAtomicsFolder/T1027.002/bin/darwin/test_upx|


#### Attack Commands: Run with `sh`! 


```sh
cp #{bin_path} /tmp/packed_bin && /tmp/packed_bin
```

#### Cleanup Commands:
```sh
rm /tmp/packed_bin
```





<br/>
<br/>

## Atomic Test #4 - Binary packed by UPX, with modified headers
Copies and then runs a simple binary (just outputting "the cake is a lie"), that was packed by UPX.

The UPX magic number (`0x55505821`, "`UPX!`") was changed to (`0x4c4f5452`, "`LOTR`"). This prevents the binary from being detected
by some methods, and especially UPX is not able to uncompress it any more.

**Supported Platforms:** macOS


**auto_generated_guid:** 4d46e16b-5765-4046-9f25-a600d3e65e4d





#### Inputs:
| Name | Description | Type | Default Value |
|------|-------------|------|---------------|
| bin_path | Packed binary | Path | PathToAtomicsFolder/T1027.002/bin/darwin/test_upx_header_changed|


#### Attack Commands: Run with `sh`! 


```sh
cp #{bin_path} /tmp/packed_bin && /tmp/packed_bin
```

#### Cleanup Commands:
```sh
rm /tmp/packed_bin
```





<br/>
