# Reverse Engineering

### Transformation \[20 pts] \[Not Solved]

> **Description**
>
> I wonder what this really is... [enc](https://mercury.picoctf.net/static/dd6004f51362ff76f98cb8c699510f23/enc) `''.join([chr((ord(flag[i]) << 8) + ord(flag[i + 1])) for i in range(0, len(flag), 2)])`

**Solution**

a

**Flag:**&#x20;

### keygenme-py \[30 pts] \[Not Solved]

> **Description**
>
> [keygenme-trial.py](https://mercury.picoctf.net/static/0c363291c47477642c72630d68936e50/keygenme-trial.py)

**Solution**

a

**Flag:**&#x20;

### crackme-py \[30 pts]

> **Description**
>
> [crackme.py](https://mercury.picoctf.net/static/f440bf2510a28914afae2947749f2db0/crackme.py)

**Solution**

So opening up the code I noticed that their are two functions, but when ran only 1 is called. I added only 1 line of code that would print out the flag.

```
decode_secret(bezos_cc_secret)
```

**Flag: picoCTF{1|\\/|\_4\_p34||ut\_8c551048}**

### ARMssembly 0 \[40 pts] \[Not Solved]

> **Description**
>
> &#x20;What integer does this program print with arguments `4004594377` and `4110761777`? File: [chall.S](https://mercury.picoctf.net/static/006961dc756fc3f418b0dbe0a42dcee8/chall.S) Flag format: picoCTF{XXXXXXXX} -> (hex, lowercase, no 0x, and 32 bits. ex. 5614267 would be picoCTF{0055aabb})

**Solution**

a

**Flag:**&#x20;

### speeds and feeds \[50 pts] \[Not Solved]

> **Description**
>
> &#x20;There is something on my shop network running at `nc mercury.picoctf.net 28067`, but I can't tell what it is. Can you?

**Solution**

a

**Flag:**&#x20;

### Shop \[50 pts] \[Not Solved]

> **Description**
>
> &#x20;Best Stuff - Cheap Stuff, Buy Buy Buy... Store Instance: [source](https://mercury.picoctf.net/static/db20ea321ce780e69e29fd4b60e60fe0/source). The shop is open for business at `nc mercury.picoctf.net 3952`.

**Solution**

a

**Flag:**&#x20;

### ARMssembly 1 \[70 pts] \[Not Solved]

> **Description**
>
> &#x20;For what argument does this program print \`win\` with variables `83`, `0` and `3`? File: [chall\_1.S](https://mercury.picoctf.net/static/b4fd1dabc9dec63c37180b5b05783b55/chall_1.S) Flag format: picoCTF{XXXXXXXX} -> (hex, lowercase, no 0x, and 32 bits. ex. 5614267 would be picoCTF{0055aabb})

**Solution**

a

**Flag:**&#x20;

### ARMssembly 2 \[90 pts] \[Not Solved]

> **Description**
>
> &#x20;What integer does this program print with argument `3297082261`? File: [chall\_2.S](https://mercury.picoctf.net/static/397a4b46a393eda0777f925f1a866f90/chall_2.S) Flag format: picoCTF{XXXXXXXX} -> (hex, lowercase, no 0x, and 32 bits. ex. 5614267 would be picoCTF{0055aabb})

**Solution**

a

**Flag:**&#x20;

### Hurry up! Wait ! \[100 pts] \[Not Solved]

> **Description**
>
> [svchost.exe](https://mercury.picoctf.net/static/7163c5d64bc60b4d079422da5c5e5053/svchost.exe)

**Solution**

a

**Flag:**&#x20;

### gogo \[110 pts] \[Not Solved]

> **Description**
>
> &#x20;Hmmm this is a weird file... [enter\_password](https://mercury.picoctf.net/static/eb7ca66cba87f2df20ea754c89148343/enter_password). There is a instance of the service running at `mercury.picoctf.net:34256`.

**Solution**

a

**Flag:**&#x20;

### ARMssembly 3 \[130 pts] \[Not Solved]

> **Description**
>
> &#x20;What integer does this program print with argument `4012702611`? File: [chall\_3.S](https://mercury.picoctf.net/static/9fdd746aed67479ab23642b1149c70aa/chall_3.S) Flag format: picoCTF{XXXXXXXX} -> (hex, lowercase, no 0x, and 32 bits. ex. 5614267 would be picoCTF{0055aabb})

**Solution**

a

**Flag:**&#x20;

### Let's get dynamic \[150 pts] \[Not Solved]

> **Description**
>
> &#x20;Can you tell what this file is reading? [chall.S](https://mercury.picoctf.net/static/474c53d8354545efbc0498791b9d9aef/chall.S)

**Solution**

a

**Flag:**&#x20;

### Easy as GDB \[160 pts] \[Not Solved]

> **Description**
>
> &#x20;The flag has got to be checked somewhere... File: [brute](https://mercury.picoctf.net/static/02142a2292c67ace2fe4ef82280ac907/brute)

**Solution**

a

**Flag:**&#x20;

### ARMssembly 4 \[170 pts] \[Not Solved]

> **Description**
>
> &#x20;What integer does this program print with argument `3459413018`? File: [chall\_4.S](https://mercury.picoctf.net/static/14c05cb93b965abb045e9b565d61931e/chall_4.S) Flag format: picoCTF{XXXXXXXX} -> (hex, lowercase, no 0x, and 32 bits. ex. 5614267 would be picoCTF{0055aabb})

**Solution**

a

**Flag:**&#x20;

### Powershelly \[180 pts] \[Not Solved]

> **Description**
>
> &#x20;It's not a bad idea to learn to read Powershell. We give you the output, but do you think you can find the input? [rev\_PS.ps1](https://mercury.picoctf.net/static/64180dd699923792daa2806cf90b1bcf/rev_PS.ps1) [output.txt](https://mercury.picoctf.net/static/64180dd699923792daa2806cf90b1bcf/output.txt)

**Solution**

a

**Flag:**&#x20;

### Rolling My Own \[300 pts] \[Not Solved]

> **Description**
>
> &#x20;I don't trust password checkers made by other people, so I wrote my own. It doesn't even need to store the password! If you can crack it I'll give you a flag. [remote](https://mercury.picoctf.net/static/c4951a16150471875346d4a3cfddc703/remote) `nc mercury.picoctf.net 47110`

**Solution**

a

**Flag:**&#x20;

### Checkpass \[375 pts] \[Not Solved]

> **Description**
>
> &#x20;What is the password? File: [checkpass](https://mercury.picoctf.net/static/dae13be1822da155932b6bdef8ebdeba/checkpass) Flag format: picoCTF{...}

**Solution**

a

**Flag:**&#x20;