Programming VIP

preface The HashSet and Hashtable used by both CC6 and CC7 chains of ysoserial deserialization vulnerability exploitation tool are hash table based data storage structures. When it comes to hash table, the HashMap class is the most used hash table storage structure in Java. At the same time, HashMap class is also the underlying implementation ...

Solemnly declare: This note is only prepared for the purpose of improving safety knowledge and sharing safety knowledge with more people. Do not use the technology in the note for illegal activities. The consequences caused by using the technology in the note have nothing to do with the author himself. We advocate that everyone is responsible f ...

ConcurrentHashMap is a multi-threaded version of HashMap. HashMap will have various problems during concurrent operation, such as dead circulation, data coverage and so on. These problems can be perfectly solved by using ConcurrentHashMap. Here's the problem. How does ConcurrentHashMap ensure thread safety? How is its bottom layer realized? Nex ...

What is empty security?? Under what circumstances is it safe to use empty space? What version? Since Flutter 2, Flutter has enabled null security by default in the configuration. By incorporating null checking into the type system, these errors can be caught during the development process, so as to prevent the crash caused by the reproduction ...

1. Introduction to JumpServer Jumpserver is the world's first open source fortress machine, developed and open source by flying to cloud Internet company. "Fortress machine" is also called operation and maintenance security audit system. The core function of jumpserver is 4a. It uses GNU GPL v2 0 open source protocol, which is ...

Problem discovery When writing a poc plug-in for reading arbitrary files at one time, the author found that using the burp replay package function can easily reproduce the vulnerability, but using *. Written in python However, the py script cannot successfully output the result of success.Looking at the python script again, I fell into a long ...

Test environment: jdk1.8(jdk8u71) Commons Collections4.0 HashSet HashSet uses the data structure of the Hash table. The time complexity of adding, deleting, modifying and querying is O(1). Set is a set. The elements are not added in order, and there will be no duplicate elements in the set. Combined with this, we can roughly know the ...

ConcurrentHashMap is a multi-threaded version of HashMap. HashMap will have various problems during concurrent operation, such as dead circulation, data coverage and so on. These problems can be perfectly solved by using ConcurrentHashMap. Here's the problem. How does ConcurrentHashMap ensure thread safety? How is its bottom layer realized? ...

Apache common collections with Java deserialization vulnerability Gongzong No.: Black palm A blogger who focuses on sharing network security, hot spots in the hacker circle and hacker tool technology area! preface: Recently, I calmed down and read a lot of Daniel's notes and blogs. I have gained a lot, so I'd like to record the first ...

This article is the third of my study notes on reverse cracking shelling in the great God forum. It is my review and summary of what I have learned in the past. There may be fallacies. You are welcome to point out. Notes will be released one after another, hoping to help Mengxin who wants to get started and make progress together 32-bit gener ...