{"id":7044,"date":"2014-10-28T11:26:30","date_gmt":"2014-10-28T11:26:30","guid":{"rendered":"https:\/\/www.techopedia.com\/definition\/polymorphic-malware\/"},"modified":"2019-06-11T15:05:13","modified_gmt":"2019-06-11T15:05:13","slug":"polymorphic-malware","status":"publish","type":"definition","link":"https:\/\/www.techopedia.com\/definition\/13674\/polymorphic-malware","title":{"rendered":"Polymorphic Malware"},"content":{"rendered":"

What Does Polymorphic Malware Mean?<\/span><\/h2>\n

Polymorphic malware is a type of malware that constantly morphs, evolves, or changes appearance to make it difficult for anti-malware programs to detect it.<\/p>\n

The evolution of the malware\u2019s code usually occurs in different ways, such as changing the filename and performing encryption using variable keys. Polymorphic malware comes in the usual forms such as viruses, Trojans, worms or spyware.<\/p>\n

Techopedia Explains Polymorphic Malware<\/span><\/h2>\n

The polymorphism in the code of polymorphic malware is meant to evade the pattern-matching detection that is done by security and anti-malware organizations during the investigative and detection process.<\/p>\n

Polymorphic in this context simply means “to change the appearance of” and is just meant to delay detection and not really evade it completely since the actions of the malware remain the same. It could still be detected through various signatures using memory-based signature detection or behavioral analysis techniques deployed by modern antivirus software<\/a>.<\/p>\n

To create a polymorphic malware, a mutation engine is bundled with the malware or other self-propagating code. The mutation engine then changes the appearance of the malware through encryption or by appending or pre-pending data.<\/p>\n","protected":false},"excerpt":{"rendered":"

What Does Polymorphic Malware Mean? Polymorphic malware is a type of malware that constantly morphs, evolves, or changes appearance to make it difficult for anti-malware programs to detect it. The evolution of the malware\u2019s code usually occurs in different ways, such as changing the filename and performing encryption using variable keys. Polymorphic malware comes in […]<\/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],"class_list":["post-7044","definition","type-definition","status-publish","format-standard","hentry","definitioncat-cybersecurity"],"acf":[],"yoast_head":"\nWhat is Polymorphic Malware? - Definition from Techopedia<\/title>\n<meta name=\"description\" content=\"This definition explains the meaning of Polymorphic Malware 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=\"Polymorphic Malware\" \/>\n<meta property=\"og:description\" content=\"This definition explains the meaning of Polymorphic Malware and why it matters.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.techopedia.com\/definition\/13674\/polymorphic-malware\" \/>\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=\"2019-06-11T15:05:13+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=\"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\/13674\/polymorphic-malware#article\",\"isPartOf\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/13674\/polymorphic-malware\"},\"author\":{\"name\":\"Margaret Rouse\",\"@id\":\"https:\/\/www.techopedia.com\/#\/schema\/person\/f5dd538e31ee352d105b8af36c4268a5\"},\"headline\":\"Polymorphic Malware\",\"datePublished\":\"2014-10-28T11:26:30+00:00\",\"dateModified\":\"2019-06-11T15:05:13+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/13674\/polymorphic-malware\"},\"wordCount\":190,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/www.techopedia.com\/#organization\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\/\/www.techopedia.com\/definition\/13674\/polymorphic-malware#respond\"]}],\"articleSection\":\"\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/13674\/polymorphic-malware\",\"url\":\"https:\/\/www.techopedia.com\/definition\/13674\/polymorphic-malware\",\"name\":\"What is Polymorphic Malware? 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