Author: Orange Tsai(@orange_8361) P.S. This is a cross-post blog from DEVCORE The series of A New Attack Surface on MS Exchange:A New Attack Surface on MS Exchange Part 1 - ProxyLogon!A New Attack Surface on MS Exchange Part 2 - ProxyOracle!A New Attack Surface on MS Exchange Part 3 - ProxyShell!A New Attack Surface on MS Exchange Part 4 - ProxyRelay!

Author: Orange Tsai(@orange_8361) and Meh Chang(@mehqq_) P.S. This is a cross-post blog from DEVCORE Hi, this is the last part of Attacking SSL VPN series. If you haven’t read previous articles yet, here are the quick links for you: Infiltrating Corporate Intranet Like NSA: Pre-auth RCE on Leading SSL VPNs Attacking SSL VPN - Part 1: PreAuth RCE on Palo Alto GlobalProtect, with Uber as

在 Web Security 中，我喜歡伺服器端的漏洞更勝於客戶端的漏洞!(當然可以直接拿 shell 的客戶端洞不在此限XD) 因為可以直接控制別人的伺服器對我來說更有趣! 正因如此，我以往的文章對於 XSS 及 CSRF 等相關弱點也較少著墨(仔細翻一下也只有 2018 年 Google CTF 那篇XD)，剛好這次的漏洞小小有趣，秉持著教育及炫耀(?)的心態就來發個文了XD 最近需要自架共筆伺服器，調查了一些市面上支援 Markdown 的共筆平台，最後還是選擇了國產的 HackMD! 當然，對於自己要使用的軟體都會習慣性的檢視一下安全性，否則怎麼敢放心使用? 因此花了約半天對 HackMD 進行了一次原始碼檢測(Code Review)! HackMD 是一款由台灣人自行研發的線上 Markdown 共筆系統，除了在台灣資訊圈流行外，也被許多台灣研討會如 COSCUP,

In every year’s HITCON CTF, I will prepare at least one PHP exploit challenge which the source code is very straightforward, short and easy to review but hard to exploit! I have put all my challenges in this GitHub repo you can check, and here are some lists :P 2017 Baby^H Master PHP 2017 (0/1541 solved) Phar protocol to deserialize malicious object Hardcode anonymous function

Hi! This is the case study in my Black Hat USA 2018 and DEFCON 26 talk, you can also check slides here: Breaking Parser Logic! Take Your Path Normalization Off and Pop 0days Out In past two years, I started to pay more attention on the “inconsistency” bug. What's that? It’s just like my SSRF talk in Black Hat and GitHub SSRF to RCE case last year, finding inconsistency between the URL parser

gCalc is the web challenge in Google CTF 2018 quals and only 15 teams solved during 2 days’ competition! This challenge is a very interesting challenge that give me lots of fun. I love the challenge that challenged your exploit skill instead of giving you lots of code to find a simple vulnerability or guessing without any hint. So that I want to write a writeup to note this :P The challenge

打 CTF 打膩覺得沒啥新鮮感嗎，來試試打掉整個 CTF 計分板吧! 前幾個月，剛好看到某個大型 CTF 比賽開放註冊，但不允許台灣參加有點難過 :(看著官網最下面發現是 FlappyPig 所主辦，又附上 GitHub 原始碼 秉持著練習 Java code review 的精神就 git clone 下來找洞了! (以下測試皆在 FlappyPig 的允許下友情測試，漏洞回報官方後也經過同意發文)在有原始碼的狀況下進行 Java 的 code review 第一件事當然是去了解第三方 Libraries 的相依性，關於 Java 的生態系我也在幾年前的文章小小分享過，當有個底層函式庫出現問題時是整個上層的應用皆受影響!從 pom.xml 觀察發現用了Spring Framework 4.2.4從版本來看似乎很棒沒什麼重大問題

Author: Orange Tsai(@orange_8361) from DEVCORE Recently, I reviewed several Web frameworks and language implementations, and found some vulnerabilities. This is an simple and interesting case, and seems easy to exploit in real world! Affected All PHP version PHP 5 < 5.6.33 PHP 7.0 < 7.0.27 PHP 7.1 < 7.1.13 PHP 7.2 < 7.2.1 Vulnerability Details The vulnerability is on the

Hi, it’s been a long time since my last blog post. In the past few months, I spent lots of time preparing for the talk of Black Hat USA 2017 and DEF CON 25. Being a Black Hat and DEFCON speaker is part of my life goal ever. This is also my first English talk in such formal conferences. It's really a memorable experience :P Thanks Review Boards for the acceptance. This post is a simple

Before GitHub Enterprise is the on-premises version of GitHub.com that you can deploy a whole GitHub service in your private network for businesses. You can get 45-days free trial and download the VM from enterprise.github.com. After you deployed, you will see like bellow: Now, I have all the GitHub environment in a VM. It's interesting, so I decided to look deeper into VM :P

本來這篇文章叫做 HITCON CTF 2016 初賽出題小記的，可是擺著擺著就兩個月過去惹～ 轉來寫寫跟 Java 有關的東西XD 關於序今年五六月的時候，看到某個曾經很多人用但快停止維護的 Java Web Framework 弱點的修補方式感覺還有戲所以開始追一下原始碼挖 0-Day，順便整理一下 Java Web 相關弱點 — 😊覺得有趣。 通常自己在外面演講時對於 Web Security 的分類中大致可分為三個世界: File-Based 的世界，一個檔案對應一個入口點如經典的 ASP, PHP, ASPX 等 Route-Based 的世界，一個路徑對應一組函數(功能)如經典的 Rails, NodeJS, Django 等 Java 的世界，Java 的世界極其複雜自成一格獨立討論 當然三種分類並不是獨立開來，如常見 PHP MVC 用 Rewrite 將

把出過的 CTF Web 題都整理上 GitHub 惹，包括原始碼、解法、所用到技術、散落在外的 Write ups 等等 This is the repository of CTF Web challenges I made. It contains challs's source code, solution, write ups and some idea explanation. Hope you will like it :) https://github.com/orangetw/My-CTF-Web-Challenges

This is my talk about being a Bug Bounty Hunter at HITCON Community 2016 It shared some of my views on finding bugs and some case studies, such as Facebook Remote Code Execution... more details Uber Remote Code Execution... more details developer.apple.com Remote Code Execution abs.apple.com Remote Code Execution b.login.yahoo.com Remote Code Execution... more details eBay SQL Injection