{"id":13184,"date":"2014-01-06T13:19:23","date_gmt":"2014-01-06T13:19:23","guid":{"rendered":"https:\/\/www.techopedia.com\/definition\/zero-day\/"},"modified":"2014-01-06T13:19:23","modified_gmt":"2014-01-06T13:19:23","slug":"zero-day","status":"publish","type":"definition","link":"https:\/\/www.techopedia.com\/definition\/29736\/zero-day","title":{"rendered":"Zero Day"},"content":{"rendered":"<h2><span id=\"what_does_zero_day_mean\">What Does Zero Day Mean?<\/span><\/h2>\n<p>Zero day, in IT, refers to the first day that something is known or anticipated. This term is applied in various ways: for example, the first day that a team of security workers or other party discovers a virus, it is called a &quot;zero day&quot; virus. In other words, zero day is that first day that someone identifies a problem and tries to address a security threat or other IT issue.<\/p>\n<h2><span id=\"techopedia_explains_zero_day\">Techopedia Explains Zero Day<\/span><\/h2>\n<p>In addition to a &quot;zero day virus,&quot; IT professionals may talk about a &quot;zero day attack&quot; or a &quot;zero day threat.&quot; Zero day is used as a benchmark: often, security teams continue to keep careful track of the number of days that a security issue has been addressed. This is usually done in order to track progress, until a security issue or other IT issue is resolved or closed.<\/p>\n<p>Another role of the term &quot;zero day&quot; is to describe the processes that security workers encounter. Someone might talk about how many &quot;zero day&quot; attacks or threats they found on a given day. Another example is of specific &quot;zero day&quot; vulnerabilities found in the workings of an operating system. As a core software resource, the operating system has a lot of context, and that means that zero day issues carry a lot of this context also. The kinds of new security problems that pros find can be politicized, and affect an OS brand while generating the same kinds of controversy and collaborative fixes that other zero day finds typically involve.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>What Does Zero Day Mean? Zero day, in IT, refers to the first day that something is known or anticipated. This term is applied in various ways: for example, the first day that a team of security workers or other party discovers a virus, it is called a &quot;zero day&quot; virus. In other words, zero [&hellip;]<\/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":[255,218],"class_list":["post-13184","definition","type-definition","status-publish","format-standard","hentry","definitioncat-cyber-threats","definitioncat-cybersecurity"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v24.2 (Yoast SEO v24.5) - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>What is Zero Day? - Definition from Techopedia<\/title>\n<meta name=\"description\" content=\"This definition explains the meaning of Zero Day 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\" \/>\n<meta property=\"og:description\" content=\"This definition explains the meaning of Zero Day and why it matters.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.techopedia.com\/definition\/29736\/zero-day\" \/>\n<meta property=\"og:site_name\" content=\"Techopedia\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/techopedia\/\" \/>\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=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/29736\/zero-day#article\",\"isPartOf\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/29736\/zero-day\"},\"author\":{\"name\":\"Margaret Rouse\",\"@id\":\"https:\/\/www.techopedia.com\/#\/schema\/person\/f5dd538e31ee352d105b8af36c4268a5\"},\"headline\":\"Zero Day\",\"datePublished\":\"2014-01-06T13:19:23+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/29736\/zero-day\"},\"wordCount\":275,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/www.techopedia.com\/#organization\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\/\/www.techopedia.com\/definition\/29736\/zero-day#respond\"]}],\"articleSection\":\"\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/29736\/zero-day\",\"url\":\"https:\/\/www.techopedia.com\/definition\/29736\/zero-day\",\"name\":\"What is Zero Day? 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