# Firmware

> Router firmware is a nice target to start your bug hunting journey. But you have to first understand how the firmware is loaded.
>
> There is always a file in the firmware image that tells the router what services to start. Find this file.
>
> MD5 (firmware.img.gz) = 488d36e3855f16972adec9067ca6deb2
>
> **Author:** daniellimws

There are **TWO** ways to solve this challenge, and we will show both!

### Solution 1

For this challenge, we were given an `.img` file, so the first this we did was open it with [7zip](https://www.7-zip.org/download.html), and took a look inside. We noticed there was a bunch of folders inside and so we extracted it.

![](/files/k1u2DFGPJZTssZNmJBu5)

Given the challenge description, it gave us a hint on where to look for! In this case, it is the `/etc/inittab`. The [inittab](https://docs.oracle.com/cd/E19683-01/806-4073/6jd67r96e/index.html) tells the router what processes to start, and what actions to take when it starts! 

Looking inside that folder, we found the flag!! 

![flag!!](/files/Y644hhgLJkacFPVPD6oD)

Flag: `grey{inittab_1s_4n_1mp0rt4nt_p14c3_t0_100k_4t_wh3n_r3v3rs1ng_f1rmw4r3}`

### Solution 2

After extracting the folders out, we can run a [PowerShell](https://docs.microsoft.com/en-us/powershell/scripting/overview?view=powershell-7.2) command that recursively search/find a string it directories, subdirectories and files! 

```powershell
Get-ChildItem -Path PATH_TO_YOUR_DIRECTORY -recurse 
| Select-String -Pattern "grey"
```

![PowerShell command](/files/iq4LJne3hHB8P6MEC33a)

Flag: `grey{inittab_1s_4n_1mp0rt4nt_p14c3_t0_100k_4t_wh3n_r3v3rs1ng_f1rmw4r3}`

Who updates their firmware anyway? Ain't nobody got time for that! :penguin: 

![](/files/2wMRWgMqU6LYTXDsXSjq)


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