{"id":231163,"date":"2026-02-12T05:30:13","date_gmt":"2026-02-12T11:30:13","guid":{"rendered":"https:\/\/lifeboat.com\/blog\/2026\/02\/first-malicious-outlook-add-in-found-stealing-4000-microsoft-credentials"},"modified":"2026-02-12T05:30:13","modified_gmt":"2026-02-12T11:30:13","slug":"first-malicious-outlook-add-in-found-stealing-4000-microsoft-credentials","status":"publish","type":"post","link":"https:\/\/lifeboat.com\/blog\/2026\/02\/first-malicious-outlook-add-in-found-stealing-4000-microsoft-credentials","title":{"rendered":"First Malicious Outlook Add-In Found Stealing 4,000+ Microsoft Credentials"},"content":{"rendered":"<p><a class=\"aligncenter blog-photo\" href=\"https:\/\/lifeboat.com\/blog.images\/first-malicious-outlook-add-in-found-stealing-4000-microsoft-credentials.jpg\"><\/a><\/p>\n<p>Cybersecurity researchers have discovered what they said is the first known malicious Microsoft Outlook add-in detected in the wild.<\/p>\n<p>In this unusual supply chain attack <a href=\"https:\/\/www.koi.ai\/blog\/agreetosteal-the-first-malicious-outlook-add-in-leads-to-4-000-stolen-credentials\" rel=\"noopener\" target=\"_blank\">detailed<\/a> by Koi Security, an unknown attacker claimed the domain associated with a now-abandoned legitimate add-in to serve a fake Microsoft login page, stealing over 4,000 credentials in the process. The activity has been codenamed <strong>AgreeToSteal<\/strong> by the cybersecurity company.<\/p>\n<p>The Outlook add-in in question is <a href=\"https:\/\/marketplace.microsoft.com\/en-us\/product\/WA200004949\" rel=\"noopener\" target=\"_blank\">AgreeTo<\/a>, which is advertised by its developer as a way for users to connect different calendars in a single place and share their availability through email. The add-in was last updated in December 2022.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Cybersecurity researchers have discovered what they said is the first known malicious Microsoft Outlook add-in detected in the wild. In this unusual supply chain attack detailed by Koi Security, an unknown attacker claimed the domain associated with a now-abandoned legitimate add-in to serve a fake Microsoft login page, stealing over 4,000 credentials in the process. [\u2026]<\/p>\n","protected":false},"author":427,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[34],"tags":[],"class_list":["post-231163","post","type-post","status-publish","format-standard","hentry","category-cybercrime-malcode"],"_links":{"self":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/231163","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/users\/427"}],"replies":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/comments?post=231163"}],"version-history":[{"count":0,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/231163\/revisions"}],"wp:attachment":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/media?parent=231163"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/categories?post=231163"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/tags?post=231163"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}