What characterizes a zero-day exploit?

What characterizes a zero-day exploit?

• A. It is widely known to the public
• B. It is a cyber vulnerability known to the software vendor
• C. It is unknown to the software vendor
• D. It involves outdated software

Answer: (C)

A zero-day exploit centers on a vulnerability that the software vendor does not know about yet. Because the vendor is unaware, there is no patch or fix available, and defenders typically have little to no ready-made signatures or mitigations. The term reflects the fact that there were zero days to respond before attackers could exploit it. Once the vendor learns of the flaw and releases a patch, it’s no longer a zero-day. The other descriptions describe scenarios where a fix exists, is public knowledge, or the software is simply outdated, none of which capture the defining situation of a zero-day.

A zero-day exploit centers on a vulnerability that the software vendor does not know about yet. Because the vendor is unaware, there is no patch or fix available, and defenders typically have little to no ready-made signatures or mitigations. The term reflects the fact that there were zero days to respond before attackers could exploit it. Once the vendor learns of the flaw and releases a patch, it’s no longer a zero-day. The other descriptions describe scenarios where a fix exists, is public knowledge, or the software is simply outdated, none of which capture the defining situation of a zero-day.