Cryptanalysis refers to the process of analyzing information systems in order to understand hidden aspects of the systems. Cryptanalysis is used to breach cryptographic security systems and gain access to the contents of encrypted messages, even if the cryptographic key is unknown.
In the field of computer security, independent researchers often discover flaws in software that can be abused to cause unintended behaviour; these flaws are called vulnerabilities. The process by which the analysis of these vulnerabilities is shared with third parties is the subject of much debate, and is referred to as the researcher's disclosure policy. Full disclosure is the practice of publishing analysis of software vulnerabilities as early as possible, making the data accessible to everyone without restriction. The primary purpose of widely disseminating information about vulnerabilities is so that potential victims are as knowledgeable as those who attack them.
A hacker is a person skilled in information technology who achieves goals by non-standard means. The term has become associated in popular culture with a security hacker – someone with knowledge of bugs or exploits to break into computer systems and access data which would otherwise be inaccessible to them. In a positive connotation, though, hacking can also be utilized by legitimate figures in legal situations. For example, law enforcement agencies sometimes use hacking techniques to collect evidence on criminals and other malicious actors. This could include using anonymity tools to mask their identities online and pose as criminals.
In security engineering, security through obscurity is the practice of concealing the details or mechanisms of a system to enhance its security. This approach relies on the principle of hiding something in plain sight, akin to a magician's sleight of hand or the use of camouflage. It diverges from traditional security methods, such as physical locks, and is more about obscuring information or characteristics to deter potential threats. Examples of this practice include disguising sensitive information within commonplace items, like a piece of paper in a book, or altering digital footprints, such as spoofing a web browser's version number. While not a standalone solution, security through obscurity can complement other security measures in certain scenarios.
Kerckhoffs's principle of cryptography was stated by Dutch-born cryptographer Auguste Kerckhoffs in the 19th century. The principle holds that a cryptosystem should be secure, even if everything about the system, except the key, is public knowledge. This concept is widely embraced by cryptographers, in contrast to security through obscurity, which is not.
In cryptography, a brute-force attack consists of an attacker submitting many passwords or passphrases with the hope of eventually guessing correctly. The attacker systematically checks all possible passwords and passphrases until the correct one is found. Alternatively, the attacker can attempt to guess the key which is typically created from the password using a key derivation function. This is known as an exhaustive key search. This approach doesn't depend on intellectual tactics; rather, it relies on making several attempts.
In computer networking, a proxy server is a server application that acts as an intermediary between a client requesting a resource and the server providing that resource. It improves privacy, security, and possibly performance in the process.
Cross-site scripting (XSS) is a type of security vulnerability that can be found in some web applications. XSS attacks enable attackers to inject client-side scripts into web pages viewed by other users. A cross-site scripting vulnerability may be used by attackers to bypass access controls such as the same-origin policy. During the second half of 2007, XSSed documented 11,253 site-specific cross-site vulnerabilities, compared to 2,134 "traditional" vulnerabilities documented by Symantec. XSS effects vary in range from petty nuisance to significant security risk, depending on the sensitivity of the data handled by the vulnerable site and the nature of any security mitigation implemented by the site's owner network.
RSA SecurID, formerly referred to as SecurID, is a mechanism developed by RSA for performing two-factor authentication for a user to a network resource.
Wi-Fi Protected Access (WPA), Wi-Fi Protected Access 2 (WPA2), and Wi-Fi Protected Access 3 (WPA3) are the three security certification programs developed after 2000 by the Wi-Fi Alliance to secure wireless computer networks. The Alliance defined these in response to serious weaknesses researchers had found in the previous system, Wired Equivalent Privacy (WEP).
In cryptography, a timing attack is a side-channel attack in which the attacker attempts to compromise a cryptosystem by analyzing the time taken to execute cryptographic algorithms. Every logical operation in a computer takes time to execute, and the time can differ based on the input; with precise measurements of the time for each operation, an attacker can work backwards to the input. Finding secrets through timing information may be significantly easier than using cryptanalysis of known plaintext, ciphertext pairs. Sometimes timing information is combined with cryptanalysis to increase the rate of information leakage.
Privilege escalation is the act of exploiting a bug, a design flaw, or a configuration oversight in an operating system or software application to gain elevated access to resources that are normally protected from an application or user. The result is that an application or user with more privileges than intended by the application developer or system administrator can perform unauthorized actions.
Single sign-on (SSO) is an authentication scheme that allows a user to log in with a single ID to any of several related, yet independent, software systems.
A penetration test, colloquially known as a pentest, is an authorized simulated cyberattack on a computer system, performed to evaluate the security of the system; this is not to be confused with a vulnerability assessment. The test is performed to identify weaknesses, including the potential for unauthorized parties to gain access to the system's features and data, as well as strengths, enabling a full risk assessment to be completed.
Secure by design, in software engineering, means that software products and capabilities have been designed to be foundationally secure.
BitLocker is a full volume encryption feature included with Microsoft Windows versions starting with Windows Vista. It is designed to protect data by providing encryption for entire volumes. By default, it uses the Advanced Encryption Standard (AES) algorithm in cipher block chaining (CBC) or "xor–encrypt–xor (XEX)-based Tweaked codebook mode with ciphertext Stealing" (XTS) mode with a 128-bit or 256-bit key. CBC is not used over the whole disk; it is applied to each individual sector.
Open-source software security is the measure of assurance or guarantee in the freedom from danger and risk inherent to an open-source software system.
A distributed firewall is a security application on a host machine of a network that protects the servers and user machines of its enterprise's networks against unwanted intrusion. A firewall is a system or group of systems that implements a set of security rules to enforce access control between two networks to protect the "inside" network from the "outside" network. They filter all traffic regardless of its origin—the Internet or the internal network. Usually deployed behind the traditional firewall, they provide a second layer of defense. The advantages of the distributed firewall allow security rules (policies) to be defined and pushed out on an enterprise-wide basis, which is necessary for larger enterprises.
A downgrade attack, also called a bidding-down attack, or version rollback attack, is a form of cryptographic attack on a computer system or communications protocol that makes it abandon a high-quality mode of operation in favor of an older, lower-quality mode of operation that is typically provided for backward compatibility with older systems. An example of such a flaw was found in OpenSSL that allowed the attacker to negotiate the use of a lower version of TLS between the client and server. This is one of the most common types of downgrade attacks. Opportunistic encryption protocols such as STARTTLS are generally vulnerable to downgrade attacks, as they, by design, fall back to unencrypted communication. Websites which rely on redirects from unencrypted HTTP to encrypted HTTPS can also be vulnerable to downgrade attacks, as the initial redirect is not protected by encryption.
Operational technology (OT) is hardware and software that detects or causes a change, through the direct monitoring and/or control of industrial equipment, assets, processes and events. The term has become established to demonstrate the technological and functional differences between traditional information technology (IT) systems and industrial control systems environment, the so-called "IT in the non-carpeted areas".
