Malware is any software intentionally designed to cause disruption to a computer, server, client, or computer network, leak private information, gain unauthorized access to information or systems, deprive access to information, or which unknowingly interferes with the user's computer security and privacy. Researchers tend to classify malware into one or more sub-types.
In computing, a Trojan horse is any malware that misleads users of its true intent by disguising itself as a standard program. The term is derived from the ancient Greek story of the deceptive Trojan Horse that led to the fall of the city of Troy.
A rootkit is a collection of computer software, typically malicious, designed to enable access to a computer or an area of its software that is not otherwise allowed and often masks its existence or the existence of other software. The term rootkit is a compound of "root" and the word "kit". The term "rootkit" has negative connotations through its association with malware.
In computing, the superuser is a special user account used for system administration. Depending on the operating system (OS), the actual name of this account might be root, administrator, admin or supervisor. In some cases, the actual name of the account is not the determining factor; on Unix-like systems, for example, the user with a user identifier (UID) of zero is the superuser, regardless of the name of that account; and in systems which implement a role-based security model, any user with the role of superuser can carry out all actions of the superuser account. The principle of least privilege recommends that most users and applications run under an ordinary account to perform their work, as a superuser account is capable of making unrestricted, potentially adverse, system-wide changes.
Antivirus software, also known as anti-malware, is a computer program used to prevent, detect, and remove malware.
Linux malware includes viruses, Trojans, worms and other types of malware that affect the Linux family of operating systems. Linux, Unix and other Unix-like computer operating systems are generally regarded as very well-protected against, but not immune to, computer viruses.
The printing subsystem of UNIX System V is one of several standardized systems for printing on Unix, and is typical of commercial System V-based Unix versions such as Solaris and SCO OpenServer. A system running this print architecture could traditionally be identified by the use of the user command lp as the primary interface to the print system, as opposed to the BSD lpr command.
fstab is a system file commonly found in the directory /etc on Unix and Unix-like computer systems. In Linux, it is part of the util-linux package. The fstab file typically lists all available disk partitions and other types of file systems and data sources that may not necessarily be disk-based, and indicates how they are to be initialized or otherwise integrated into the larger file system structure.
ClamAV (antivirus) is a free software, cross-platform antimalware toolkit able to detect many types of malware, including viruses. It was developed for Unix and has third party versions available for AIX, BSD, HP-UX, Linux, macOS, OpenVMS, OSF (Tru64), Solaris and Haiku. As of version 0.97.5, ClamAV builds and runs on Microsoft Windows. Both ClamAV and its updates are made available free of charge. One of its main uses is on mail servers as a server-side email virus scanner.
A hypervisor, also known as a virtual machine monitor (VMM) or virtualizer, is a type of computer software, firmware or hardware that creates and runs virtual machines. A computer on which a hypervisor runs one or more virtual machines is called a host machine, and each virtual machine is called a guest machine. The hypervisor presents the guest operating systems with a virtual operating platform and manages the execution of the guest operating systems. Unlike an emulator, the guest executes most instructions on the native hardware. Multiple instances of a variety of operating systems may share the virtualized hardware resources: for example, Linux, Windows, and macOS instances can all run on a single physical x86 machine. This contrasts with operating-system–level virtualization, where all instances must share a single kernel, though the guest operating systems can differ in user space, such as different Linux distributions with the same kernel.
rkhunter is a Unix-based tool that scans for rootkits, backdoors and possible local exploits. It does this by comparing SHA-1 hashes of important files with known good ones in online databases, searching for default directories, wrong permissions, hidden files, suspicious strings in kernel modules, and special tests for Linux and FreeBSD. rkhunter is notable due to its inclusion in popular operating systems
Kaspersky Anti-Virus is a proprietary antivirus program developed by Kaspersky Lab. It is designed to protect users from malware and is primarily designed for computers running Microsoft Windows and macOS, although a version for Linux is available for business consumers.
OSSEC (Open Source HIDS SECurity) is a free, open-source host-based intrusion detection system (HIDS). It performs log analysis, integrity checking, Windows registry monitoring, rootkit detection, time-based alerting, and active response. It provides intrusion detection for most operating systems, including Linux, OpenBSD, FreeBSD, OS X, Solaris and Windows. OSSEC has a centralized, cross-platform architecture allowing multiple systems to be easily monitored and managed. OSSEC has a log analysis engine that is able to correlate and analyze logs from multiple devices and formats.
Lynis is an extensible security audit tool for computer systems running Linux, FreeBSD, macOS, OpenBSD, Solaris, and other Unix derivatives. It assists system administrators and security professionals with scanning a system and its security defenses, with the final goal being system hardening.
Alureon is a trojan and rootkit created to steal data by intercepting a system's network traffic and searching for banking usernames and passwords, credit card data, PayPal information, social security numbers, and other sensitive user data. Following a series of customer complaints, Microsoft determined that Alureon caused a wave of BSoDs on some 32-bit Microsoft Windows systems. The update, MS10-015, triggered these crashes by breaking assumptions made by the malware author(s).
Tiger is a security software for Unix-like computer operating systems. It can be used both as a security audit tool and a host-based intrusion detection system and supports multiple UNIX platforms. Tiger is free under the GPL license and unlike other tools, it needs only of POSIX tools, and is written entirely in shell language.
Avira Operations GmbH & Co. KG is a German multinational computer security software company mainly known for its Avira Free Security antivirus software. Although founded in 2006, the Avira antivirus application has been under active development since 1986 through its predecessor company H+BEDV Datentechnik GmbH. Since 2021, Avira has been owned by American software company NortonLifeLock, which also operates Norton, Avast and AVG. It was previously owned by investment firm Investcorp.
Silvio Cesare is an Australian security researcher known for his multiple articles in phrack, talks at numerous security conferences including Defcon and Black Hat Briefings. Silvio is also a former member of w00w00. His security research includes an IDS evasion bug in the widely deployed Snort software. Silvio holds a PhD in Computer Science from Deakin University and is the co-founder of the security conference BSides Canberra. He earned his Master of Informatics and Bachelor of Information Technology from CQUniversity Australia. He currently operates the Canberra based training and consulting provider InfoSect.
Linux Malware Detect, abbreviated as LMD or maldet, is a software package that looks for malware on Linux systems and reports on it.
Drovorub is a software toolkit for developing malware for the Linux operating system. It was created by the 85th Main Special Service Center, a unit of the Russian GRU often referred to as APT28.
