SEC-T - 0x10sion

10-13th of September 2024

Badge Puzzles (no spoilers here)

SEC-T Badge Puzzle is a new tradition of pen-brain-and-paper puzzles designed to be medium hard yet annoyingly easy to over analyse. The first person to solve a badge challenge will get two free entries to SEC-T of the year(s) of their choice. Currently there are different methods for submitting your answer, either by using the same webpage your ticket was downloaded from or by emailing [email protected]

If you believe you find a bug or are in a desperate need of a hint send us an email to [email protected]. To the extent that we give answers to any elements of the puzzle these answers will also be published here for everyone to see.

Generally the following things are true for the puzzles.

2018 (Solved)

The 2018 badge challenge was delivered on an NFC tag. The challenge had a minor bug that could easily have been figured out. But  because of that we have reprinted a fixed version below (base64 to preserve the data).

2020-05-02: It came to our attention that there was several issues with this challenge and a corrected version has been published here.


The badge puzzle was also printed as a poster for SEC-T 2019. This version has issues and should not be used.

This badge was solved by Alve Björk on May 3:rd 2020

2019 (Solved)

The 2019 badge challenge was printed on one side of the plastic badge and so far no bugs have been found. This puzzle was made to be easier than 2018.


A member of audience came up to me and said they were there to “face me for two free tickets”. Clearly thinking this was the trick to winning.

I told them it wasn’t me saying this but that they instead should do what the card told them, to the card, and not to me.

Human: Who is Andy T?

SEC-T: There is no Andy T… it should be read as “and YT”

The 2019 badge was solved by Carl Sundvall on October 14:th 2019

2022 (Solved)

The 2022 badge challenge was printed on one side of the plastic badge and so far no bugs have been found. This puzzle was made to be easier than 2019.

Human: is the entire puzzle present on the badge or are there hints on the lanyard etc?

SEC-T: The entirety of the puzzle is present on the badge itself and in locations pointed to by the information in the puzzle.

The 2022 badge was solved by Team Goolickers of Unciphered with Zonk Ruehl, Jerry McGuire and Max Cohen on the 19:th of September 2022

2023 (Solved)

The SEC-T 0x0F challenge was printed on the back of the conference badge and no bugs were found. The challenge is made up of three levels and was made to be a bit more difficult that 2022.

The 2023 badge challenge was solved by Shades on 22:nd of September 2023.