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Memory Safety
Memory safety is the state of being protected from various software bugs and Vulnerability (computing), security vulnerabilities when dealing with random-access memory, memory access, such as buffer overflows and dangling pointers. For example, Java (programming language), Java is said to be memory-safe because its runtime error detection checks array bounds and pointer dereferences. In contrast, C (programming language), C and C++ allow arbitrary pointer arithmetic with pointers implemented as direct memory addresses with no provision for bounds checking, and thus are potentially memory-unsafe. History Memory errors were first considered in the context of resource management and time-sharing systems, in an effort to avoid problems such as fork bombs. Developments were mostly theoretical until the Morris worm, which exploited a buffer overflow in fingerd. The field of computer security developed quickly thereafter, escalating with multitudes of new Attack (computing), attacks s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software Bugs
A software bug is an error, flaw or fault (technology), fault in the design, development, or operation of computer software that causes it to produce an incorrect or unexpected result, or to behave in unintended ways. The process of finding and correcting bugs is termed "debugging" and often uses formal techniques or tools to pinpoint bugs. Since the 1950s, some computer systems have been designed to deter, detect or auto-correct various computer bugs during operations. Bugs in software can arise from mistakes and errors made in interpreting and extracting users' requirements, planning a program's software architecture, design, writing its source code, and from interaction with humans, hardware and programs, such as operating systems or Library (computing), libraries. A program with many, or serious, bugs is often described as ''buggy''. Bugs can trigger errors that may have ripple effects. The effects of bugs may be subtle, such as unintended text formatting, through to more o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attack (computing)
A cyberattack is any offensive maneuver that targets computer information systems, computer networks, infrastructures, or personal computer devices. An attacker is a person or process that attempts to access data, functions, or other restricted areas of the system without authorization, potentially with malicious intent. Depending on the context, cyberattacks can be part of cyber warfare or cyberterrorism. A cyberattack can be employed by sovereign states, individuals, groups, societies or organisations and it may originate from an anonymous source. A product that facilitates a cyberattack is sometimes called a cyber weapon. Cyber attacks have increased with an alarming rate for the last few years A cyberattack may steal, alter, or destroy a specified target by hacking into a susceptible system. Cyberattacks can range from installing spyware on a personal computer to attempting to destroy the infrastructure of entire nations. Legal experts are seeking to limit the use of the ter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pointer (computer Science)
In computer science, a pointer is an object in many programming languages that stores a memory address. This can be that of another value located in computer memory, or in some cases, that of memory-mapped computer hardware. A pointer ''references'' a location in memory, and obtaining the value stored at that location is known as ''dereferencing'' the pointer. As an analogy, a page number in a book's index could be considered a pointer to the corresponding page; dereferencing such a pointer would be done by flipping to the page with the given page number and reading the text found on that page. The actual format and content of a pointer variable is dependent on the underlying computer architecture. Using pointers significantly improves performance for repetitive operations, like traversing iterable data structures (e.g. strings, lookup tables, control tables and tree structures). In particular, it is often much cheaper in time and space to copy and dereference pointers than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Garbage Collection (computer Science)
In computer science, garbage collection (GC) is a form of automatic memory management. The ''garbage collector'' attempts to reclaim memory which was allocated by the program, but is no longer referenced; such memory is called '' garbage''. Garbage collection was invented by American computer scientist John McCarthy around 1959 to simplify manual memory management in Lisp. Garbage collection relieves the programmer from doing manual memory management, where the programmer specifies what objects to de-allocate and return to the memory system and when to do so. Other, similar techniques include stack allocation, region inference, and memory ownership, and combinations thereof. Garbage collection may take a significant proportion of a program's total processing time, and affect performance as a result. Resources other than memory, such as network sockets, database handles, windows, file descriptors, and device descriptors, are not typically handled by garbage collection, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Management
Memory management is a form of resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed. This is critical to any advanced computer system where more than a single process might be underway at any time. Several methods have been devised that increase the effectiveness of memory management. Virtual memory systems separate the memory addresses used by a process from actual physical addresses, allowing separation of processes and increasing the size of the virtual address space beyond the available amount of RAM using paging or swapping to secondary storage. The quality of the virtual memory manager can have an extensive effect on overall system performance. In some operating systems, e.g. OS/360 and successors, memory is managed by the operating system. In other operating systems, e.g. Unix-like operating sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Like Shooting Fish In A Barrel
In English, the word ''like'' has a very flexible range of uses, ranging from conventional to non-standard. It can be used as a noun, verb, adverb, adjective, preposition, particle, conjunction, hedge, filler, and quotative. Uses Comparisons ''Like'' is one of the words in the English language that can introduce a simile (a stylistic device comparing two dissimilar ideas). It can be used as a preposition, as in "He runs ''like'' a cheetah"; it can also be used as a suffix, as in "She acts very child-''like''. It can also be used in non-simile comparisons such as, "She has a dog ''like'' ours". As a conjunction ''Like'' is often used in place of the subordinating conjunction ''as'', or ''as if''. Examples: * They look ''like'' they have been having fun. * They look ''as if'' they have been having fun. Many people became aware of the two options in 1954, when a famous ad campaign for Winston cigarettes introduced the slogan " Winston tastes good—like a cigarette should." T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sudo
sudo ( or ) is a program for Unix-like computer operating systems that enables users to run programs with the security privileges of another user, by default the superuser. It originally stood for "superuser do", as that was all it did, and it is its most common usage; however, the official Sudo project page lists it as "su 'do'". The current Linux manual pages for su define it as "substitute user", making the correct meaning of sudo "substitute user, do", because sudo can run a command as other users as well. Unlike the similar command '' su'', users must, by default, supply their own password for authentication, rather than the password of the target user. After authentication, and if the configuration file (typically /etc/sudoers) permits the user access, the system invokes the requested command. The configuration file offers detailed access permissions, including enabling commands only from the invoking terminal; requiring a password per user or group; requiring re-entry of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heartbleed
Heartbleed was a security bug in the OpenSSL cryptography library, which is a widely used implementation of the Transport Layer Security (TLS) protocol. It was introduced into the software in 2012 and publicly disclosed in April 2014. Heartbleed could be exploited regardless of whether the vulnerable OpenSSL instance is running as a TLS server or client. It resulted from improper input validation (due to a missing bounds check) in the implementation of the TLS heartbeat extension. Thus, the bug's name derived from ''heartbeat''. The vulnerability was classified as a buffer over-read, a situation where more data can be read than should be allowed. Heartbleed was registered in the Common Vulnerabilities and Exposures database as . The federal Canadian Cyber Incident Response Centre issued a security bulletin advising system administrators about the bug. A fixed version of OpenSSL was released on 7 April 2014, on the same day Heartbleed was publicly disclosed. System administra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Google Chromium
Chromium is a free and open-source web browser project, mainly developed and maintained by Google. This codebase provides the vast majority of code for the Google Chrome browser, which is proprietary software and has some additional features. The Chromium codebase is widely used. Microsoft Edge, Samsung Internet, Opera, and many other browsers are based on the Chromium code. Moreover, significant portions of the code are used by several app frameworks. Google does not provide an official stable version of the Chromium browser, but does provide official API keys for some features, such as speech to text and translation. Licensing Chromium is a free and open-source software project. The Google-authored portion is shared under the 3-clause BSD license. Third party dependencies are subject to a variety of licenses, including MIT, LGPL, Ms-PL, and an MPL/GPL/LGPL tri-license. This licensing permits any party to build the codebase and share the resulting browser executabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Google
Google LLC () is an American multinational technology company focusing on search engine technology, online advertising, cloud computing, computer software, quantum computing, e-commerce, artificial intelligence, and consumer electronics. It has been referred to as "the most powerful company in the world" and one of the world's most valuable brands due to its market dominance, data collection, and technological advantages in the area of artificial intelligence. Its parent company Alphabet is considered one of the Big Five American information technology companies, alongside Amazon, Apple, Meta, and Microsoft. Google was founded on September 4, 1998, by Larry Page and Sergey Brin while they were PhD students at Stanford University in California. Together they own about 14% of its publicly listed shares and control 56% of its stockholder voting power through super-voting stock. The company went public via an initial public offering (IPO) in 2004. In 2015, Google was reor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft
Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washington, United States. Its best-known software products are the Windows line of operating systems, the Microsoft Office suite, and the Internet Explorer and Edge web browsers. Its flagship hardware products are the Xbox video game consoles and the Microsoft Surface lineup of touchscreen personal computers. Microsoft ranked No. 21 in the 2020 Fortune 500 rankings of the largest United States corporations by total revenue; it was the world's largest software maker by revenue as of 2019. It is one of the Big Five American information technology companies, alongside Alphabet, Amazon, Apple, and Meta. Microsoft was founded by Bill Gates and Paul Allen on April 4, 1975, to develop and sell BASIC interpreters for the Altair 8800. It rose to do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heap Spraying
In computer security, heap spraying is a technique used in exploits to facilitate arbitrary code execution. The part of the source code of an exploit that implements this technique is called a heap spray. In general, code that ''sprays the heap'' attempts to put a certain sequence of bytes at a predetermined location in the memory of a target process by having it allocate (large) blocks on the process's heap and fill the bytes in these blocks with the right values. Operation A heap spray does not actually exploit any security issues but it can be used to make a vulnerability easier to exploit. A heap spray by itself cannot be used to break any security boundaries: a separate security issue is needed. Exploiting security issues is often hard because various factors can influence this process. Chance alignments of memory and timing introduce a lot of randomness (from the attacker's point of view). A heap spray can be used to introduce a large amount of order to compensate for this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
