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Reimonware H-C0N 2023

With the 5th H-C0N 2023 cybersecurity congress held in LaNave (Madrid), some friends asked me to collaborate with a challenge for the CTF that was organised from 21 to 25 February. The congress itself deserves it and the people who organise it make an incredible effort to celebrate it, so


ASIS CTF 2020. Web Warmup.

Hello all, friends. 20 months from my last post! We could say i’m not too much active on this blog , ha-ha. This weekend had the opportunity to test some ASIS CTF 2020 challenges and join this legendary CTF with dcua team. I remember that it was more or less


CSAW. Red Team competition. «Babyrev»

Babyrev is reversing challenge on CSAW «Red team competition» where have to pass 99 rounds of input 4-digits code based on some check function.  Main graph on IDA:  Disassembly of check(): Dump of assembler code for function check: 0x0000000000400893 <+0>: push rbp 0x0000000000400894 <+1>: mov rbp,rsp 0x0000000000400897 <+4>: mov QWORD


Efiens CTF – mediumRE

Hi folks. This post is about a Efiens challenge, easy-medium RE that my colleague Cothan publish on twitter as a part of a set of them included on Efiens CTF. As described on his tweet, is an easy ctf that try to catch some talent people. I have spare time

CTF, labs, Wargame,

IHackLabs, aprende de los mejores

Introducción Recientemente he probado «IHackLabs», una plataforma de aprendizaje, laboratorios y certificaciones para estudiantes y profesionales. Me he reunido con Diana y Carlos, la gente detrás de esta idea, en «Sh3llCON2017 Congreso de Seguridad». Todo el trabajo en torno a los laboratorios están destinados a reproducir los ejercicios del mundo


LSE Epita format string

Time ago i can’t write on this blog. It’s normal when your time is full dedicated to work and study. Now, i have one hour to publish something related guess with ? Yes, ctf challenges :) Since this is only 1 point level and i think is basic for everyone


Hackover CTF – messagecenter

A long time since last writeup so i have decided comment a simple web level solved on «Hackover CTF». It’s very old vulnerability related with type safe comparation on PHP and serialize function. We have a web login with normal test users (demo, demo2) and a ‘remember login’ function that help us



WEB 1000 SATCOM Our division of foreign cyber affairs has been hard at work lately. While mapping out some obscure subnets (which we think belong to the intelligence agency that is investigating HEAVENWEB) we’ve come accross a Sattelite Communications Center. One of our employees managed to snag a copy of


n00bs CTF Labs by Infosec Institute

This time InfoSec Institute bring us the opportunity to learn a very basic concepts for n00bs on a CTF with 15 Levels. Level 1 Just browse the source and see the comment. <!– infosec_flagis_welcome –> flag: infosec_flagis_welcome Level 2 Seems we have a broken image here. Just to see binary output


Second NotSoSecure SQLiLab CTF

Dear fellow Hackers!, thanks for signing up for the 2nd SQLiLab CTF. The CTF is now on!. Before you go all out hacking the CTF, here are some rules of the engagement: 1. Strictly no brute-forcing. There is no need to brute-force anything. If we see any excessive brute-forcing attempt,


Mission 1 & Mission 2 Write-Ups – Security-BSides London

Hi all!. Last february i have participated on Security BSides Challenges, here: Yesterday @AlecRWaters contacts me to confirm that we get second position on both challenges. So got a ticket to this  infosec conference. "Hi , I’m delighted to announce that you’ve won second prize in both Challenge 1 and


PHDays 2014 Quals: PHP_JL writeup

This time another great quals CTF organized by guys and girls of PHdays. PHP_JL was another PHP with safe_mode and functions disabled. First we have to notice is the source of html output: <!– Notice: Undefined index: code in /var/www/index.php on line 53 Notice: Undefined index: code in /var/www/index.php on

CTF, Wargame, XSS,

XSS Challenges

Here’s my journal to solve all the XSS Challenges writed  by yamagata21 on, This is an starter level to people who want to learn some cross-site scripting and its several ways to inject on differents browsers. XSS Challenges Stage1: Solution: <script>alert(document.domain);</script> Stage2: Solution: «><script>alert( alert(document.domain))</script> Stage3: Solution: The input in text box

CTF, Wargame,

NotSoSecure SQLi CTF – writeup

Access to challenge using a proxy like burp or zap and submit data to login. Notice the forwarded to: that contains: 7365637265745f72656769737465722e68746d6c This could be decoded ‘7365637265745f72656769737465722e68746d6c’.decode(‘hex’) in python to read secret_register.html >>> '7365637265745f72656769737465722e68746d6c'.decode('hex') 'secret_register.html' The registration page offers four fields that, when you register, create some session_id encoded

CTF, Wargame,

29C3 CTF: Node writeup

This 29C3 from Chaos Computer Club hackers. We participate as dcua team, awesome people trying the best effort for the challenges.  Nice job! Node Points: 200 Solves: 18 Description Node.js is smart, fast, easy and secure… Don’t you think so too? Hint: google and other sites always look at one file before

CTF, Wargame,

CTF Mini Zombie Business (+100pt) write-up

We got to make some business with our zombie in There’s a zombie image and at first look we get some data encoded on it. <form/name="a"/data-a="Fcabdux ehiktgmaj:nopylqrsvf_wz(&quot;){}.?L="></form> <div/id="&#x61;"></div>//id="a" <img/src="zomb.png"/onclick="dafuq()"/> There is a <script> tag with several unescape functions and after convert it from url-encode and unicode text we get: