> For the complete documentation index, see [llms.txt](https://ctf.zeyu2001.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ctf.zeyu2001.com/2021/picoctf/trivial-flag-transfer-protocol-90.md).

# Trivial Flag Transfer Protocol (90)

## Problem

Figure out how they moved the [flag](https://mercury.picoctf.net/static/88553d672efbccbc5868002f4c6eb737/tftp.pcapng).

## Solution

In Wireshark, Export Objects > TFTP > Extract All

The program.deb installs steghide.

instructions.txt - Caesar Cipher

```
GSGCQBRFAGRAPELCGBHEGENSSVPFBJRZHFGQVFTHVFRBHESYNTGENAFSRE.SVTHERBHGNJNLGBUVQRGURSYNTNAQVJVYYPURPXONPXSBEGURCYNA
```

\=

```
TFTPDOESNTENCRYPTOURTRAFFICSOWEMUSTDISGUISEOURFLAGTRANSFER.FIGUREOUTAWAYTOHIDETHEFLAGANDIWILLCHECKBACKFORTHEPLAN
```

TFTP DOESNT ENCRYPT OUR TRAFFIC SO WE MUST DISGUISE OUR FLAG TRANSFER. FIGURE OUT A WAY TO HIDE THE FLAG AND I WILL CHECK BACK FOR THE PLAN

plan.txt - Caesar Cipher

```
VHFRQGURCEBTENZNAQUVQVGJVGU-QHRQVYVTRAPR.PURPXBHGGURCUBGBF
```

\=

```
I USED THE PROGRAM AND HID IT WITH-DUEDILIGENCE. CHECK OUT THE PHOTOS
```

Use the DUEDILIGENCE passphrase:

![](/files/-MX2kE8VyEUbY3QXVd0Y)


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