1 Jan 2019

TetCTF 19

Web - IQTest2 (unsolved) Pwn - Easy webserver (unsolved) Pwn - Babysandbox Pwn - Babyheap Pwn - Babyfirst Web IQTest2 After looking at the source code, there is a path that we can polute the $level variable to pass. It has to pass several condition check: if (isset($_COOKIE['saved']) && !empty($_COOKIE['saved']) && isset($_COOKIE['hash']) && !empty($_COOKIE['hash'])) { $saved = base64_decode($_COOKIE["saved"]); $seed = urldecode(substr($saved, 5 )); } if( md5($GLOBALS['secret'].

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30 Dec 2018

35C3 CTF

This is my first time participating in C3 CTF. Although I wasn’t able to solve many challenges within the time of the CTF, I still find the challenges really awesome and exciting. I wanted to solve pwnable challenges with the hope to learn more about exploit development of real applications, but ended up solving 2 RE ones. Here is my writeup for them :) RE - Corebot This challenge is a 32-bit Windows binary.

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29 Jun 2018

H1-702 CTF 2018

It’s this time of the year again and I have the chance to play the CTF held by Hackerone. It has a lot of mobile hacking challenge, and at the same time, I wanted to dive into this. What a good time to learn! Update 1: I totally forgot the fifth part of the flag in the first challenge while I was writing this. That’s what it’s like rushing a post :)

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22 May 2018

GRIMM HAX Combined Challenge

GRIMM HAX Combined Challenge Welcome, Bobby (100pts) Accessing the website at http://www.haxcorp.grimm-co.com/, we are provided with a login page with username as password. The objective of this level is to login as admin. Seeing this as a warmup level, I immediately try the following classic SQL injection And we are in. The flag is GRIMM-BOBBY-TABLES-WOULD-BE-PROUD. Oh How the Tables have Turned (100pts) From the description of the challenge, I predicted that this is another SQL injection to find the flag in a different table in the database, especially when we are presented with a search functionality.

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16 Dec 2017

2017 SANS Holiday Hacking Challenge

This year, I’ve had the chance to participate in SANS Holiday Hacking Challenge. The first time I did it was last year. I didn’t think it was interesting with real pentesting stuffs until I read the writeups, so I decided to start early this year. Terminal Challenges Finding Great Book Pages Things I’ve learned Terminal Challenges WINTER WONDER LANDING Linux command hijacking Click on the terminal, we are presented with the object: to find elftalkd.

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4 Dec 2017

UB Lockdown V3

Vietnamese version below English The weekend before Thanksgiving, I had the chance to play at Lockdown v3, an incident response competition held at University of Buffalo by UBNetDef. Overview This is a defense-only competition There are 6 people per team. Each team is given access to an infrastructure with basic components of an enterprise network: Windows and Linux client machines Web server(s) Active Directory/DNS server(s) FTP server Mail server Databases A router.

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20 Sep 2017

CSAW CTF 2017 Qualification

pwn: pilot (75 pts.) English version here Vietnamese Năm nay mình có cơ hội chơi CSAW CTF một cách thực sự, với hy vọng team đủ khỏe để vào final North America lần nữa. Qua một năm được các tiền bối thông não (quangltm và anh tuanit96), mình đã quẩy được vài bài khá cơ bản. Đây là bài đầu tiên mình owned trong giờ thi. Bài này là một bài buffer overflow cơ bản.

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