{"id":12142,"date":"2011-10-21T17:50:17","date_gmt":"2011-10-21T17:50:17","guid":{"rendered":"https:\/\/www.techopedia.com\/definition\/zero-day-threat\/"},"modified":"2012-11-18T10:38:23","modified_gmt":"2012-11-18T10:38:23","slug":"zero-day-threat","status":"publish","type":"definition","link":"https:\/\/www.techopedia.com\/definition\/27451\/zero-day-threat","title":{"rendered":"Zero-Day Threat"},"content":{"rendered":"

What Does Zero-Day Threat Mean?<\/span><\/h2>\n

A zero-day threat is a threat that exploits an unknown computer security vulnerability. The term is derived from the age of the exploit, which takes place before or on the first (or \u201czeroth\u201d) day of a developer\u2019s awareness of the exploit or bug. This means that there is no known security fix because developers are oblivious to the vulnerability or threat.<\/p>\n

Attackers exploit zero-day vulnerabilities through different vectors. Web browsers are the most common, due to their popularity. Attackers also send emails with attachments exploiting software attachment vulnerabilities.<\/p>\n

A zero-day threat is also known as a zero-hour attack or day-zero attack.<\/p>\n

Techopedia Explains Zero-Day Threat<\/span><\/h2>\n

Zero-day exploits are often put up by renowned hacker groups. Typically, the zero-day attack exploits a bug that neither developers, nor the users, know about. Indeed, this is exactly what the malicious coders anticipate. By discovering a software vulnerability before the software’s developers do, a hacker can make a worm or virus that can be used to exploit the vulnerability and harm computers.<\/p>\n

Not all zero-day attacks actually take place before the software developers discover the vulnerability. In certain cases, the developers discover and understand the vulnerability; however, it may take some time to develop the patch to fix it. Also, software makers may occasionally postpone a patch release to avoid flooding users with several individual updates. If the developers find that the vulnerability is not extremely dangerous, they may decide to postpone the patch release until a number of patches are collected together. Once these patches are collected, they are released as a package. However, this strategy is risky because could invite a zero-day attack.<\/p>\n

Zero-day attacks occur within a time frame, known as the vulnerability window. This extends from the first vulnerability exploit to the point at which a threat is countered. Attackers engineer malicious software (malware) to exploit common file types, compromise attacked systems and steal valuable data. Zero-day attacks are carefully implemented for maximum damage – usually in the span of one day. The vulnerability window could range from a small period to multiple years. For instance, in 2008, Microsoft revealed an Internet Explorer vulnerability that infected a few versions of Windows released during 2001. The date in which this vulnerability was initially discovered by the attacker is unknown, but the vulnerability window in such a case might have been as much as seven years.<\/p>\n","protected":false},"excerpt":{"rendered":"

What Does Zero-Day Threat Mean? A zero-day threat is a threat that exploits an unknown computer security vulnerability. The term is derived from the age of the exploit, which takes place before or on the first (or \u201czeroth\u201d) day of a developer\u2019s awareness of the exploit or bug. This means that there is no known […]<\/p>\n","protected":false},"author":7813,"featured_media":0,"comment_status":"open","ping_status":"closed","template":"","format":"standard","meta":{"_acf_changed":false,"_lmt_disableupdate":"","_lmt_disable":"","om_disable_all_campaigns":false,"footnotes":""},"definitioncat":[218,227,239,216],"class_list":["post-12142","definition","type-definition","status-publish","format-standard","hentry","definitioncat-cybersecurity","definitioncat-data-management","definitioncat-productivity-software","definitioncat-software-development"],"acf":[],"yoast_head":"\nWhat is a Zero-Day Threat? - Definition from Techopedia<\/title>\n<meta name=\"description\" content=\"This definition explains the meaning of Zero-Day Threat and why it matters.\" \/>\n<meta name=\"robots\" content=\"noindex, follow\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Zero-Day Threat\" \/>\n<meta property=\"og:description\" content=\"This definition explains the meaning of Zero-Day Threat and why it matters.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.techopedia.com\/definition\/27451\/zero-day-threat\" \/>\n<meta property=\"og:site_name\" content=\"Techopedia\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/techopedia\/\" \/>\n<meta property=\"article:modified_time\" content=\"2012-11-18T10:38:23+00:00\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:site\" content=\"@techopedia\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/27451\/zero-day-threat#article\",\"isPartOf\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/27451\/zero-day-threat\"},\"author\":{\"name\":\"Margaret Rouse\",\"@id\":\"https:\/\/www.techopedia.com\/#\/schema\/person\/f5dd538e31ee352d105b8af36c4268a5\"},\"headline\":\"Zero-Day Threat\",\"datePublished\":\"2011-10-21T17:50:17+00:00\",\"dateModified\":\"2012-11-18T10:38:23+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/27451\/zero-day-threat\"},\"wordCount\":401,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/www.techopedia.com\/#organization\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\/\/www.techopedia.com\/definition\/27451\/zero-day-threat#respond\"]}],\"articleSection\":\"\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/27451\/zero-day-threat\",\"url\":\"https:\/\/www.techopedia.com\/definition\/27451\/zero-day-threat\",\"name\":\"What is a Zero-Day Threat? 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