Here is my solution for the easy OSINT challenge Papioutai as part of the 2026 edition of the 404CTF held online by the French secret service (DGSE) and Telecom SudParis.



We will act as genealogists in this case and we are tasked to provide the following details about someone named Jean Roux :

  • his graduation year at the ENS (Ecole Normale Supérieure)
  • his birth town

We know he died during World War I in a place ending with “demanges”.

Ahlala, l’ENS, cette école qui a produit tant d’esprits savants ! Une amie aimerait que vous l’aididez à retrouver des informations sur son bisaïeul, Jean Roux, ancien Ulmien mort pour la France en 14-18 dans un lieu dont le nom finit par demanges. Saurez-vous retrouver l’année de promotion de Jean Roux, ainsi que sa ville de naissance ? Format : 404CTF{1876_saint-germain-en-hyères}

Graduation year

A yearbook is available at archicubes.ens.fr/lannuaire :

Yearbook search

Jean Roux was graduated in 1912.

Birth town

Since our target died at war between 1914 and 1918, I used the search engine located at memoiredeshommes.gouv.fr. I got around 30 search results but only one of them died in Courdemanges :

Birth and death dates

He was born in Saint-Estèphe in 1893.

🚩 Flag

404CTF{1912_saint-estephe}