Which answer best describes a computer software attack that takes advantage of a previously unpublished vulnerability?
Correct Answer: A
A zero-day (or zero-hour, or Oday, or day zero) attack or threat is a computer threat that tries to exploit computer application vulnerabilities that are unknown to others or the software developer. Zero-day exploits (actual software that uses a security hole to carry out an attack) are used or shared by attackers before the developer of the target software knows about the vulnerability. The term derives from the age of the exploit. A "zero day" attack occurs on or before the first or "zeroth" day of developer awareness, meaning the developer has not had any opportunity to distribute a security fix to users of the software. Zero-day attacks occur during the vulnerability window that exists in the time between when a vulnerability is first exploited and when software developers start to develop a counter to that threat.
For viruses, Trojans and other zero-day attacks, the vulnerability window follows this time line:
The developer creates software containing an unknown vulnerability The attacker finds the vulnerability before the developer does The attacker writes and distributes an exploit while the vulnerability is not known to the developer The developer becomes aware of the vulnerability and starts developing a fix.
The following answers are incorrect:
Exploit Attack An exploit (from the verb to exploit, in the meaning of using something to one's own advantage) is a piece of software, a chunk of data, or sequence of commands that takes advantage of a bug, glitch or vulnerability in order to cause unintended or unanticipated behavior to occur on computer software, hardware, or something electronic (usually computerised). This frequently includes such things as gaining control of a computer system or allowing privilege escalation or a denial-ofservice attack.
Vulnerability Attack There is no such thing as the term Vulnerability Attack. However a vulnerability is synonyous with a weakness, it could be bad quality of software, a weakness within your physical security, or a weakness in your policies and procedures. An attacker will take advantage of a weakness and usually use an exploit to gain access to your systems without proper authorization or privilege.
Software Crack Software cracking is the modification of software to remove or disable features which are considered undesirable by the person cracking the software, usually related to protection methods: copy protection, trial/demo version, serial number, hardware key, date checks, CD check or software annoyances like nag screens and adware.
A crack is the software tool used to remove the need to insert a serial number or activation key.
The following reference(s) were/was used to create this question: 2011, Ethical Hacking and Countermeasures, EC-Council Official Curriculum, Book 1, Page 9 https://en.wikipedia.org/wiki/Zero_day_attack https://en.wikipedia.org/wiki/Exploit_%28computer_security%29 https://en.wikipedia.org/wiki/Software_cracking
