{"id":15912,"date":"2026-04-15T03:01:53","date_gmt":"2026-04-14T18:01:53","guid":{"rendered":"https:\/\/m365jp.net\/?p=15912"},"modified":"2026-04-15T03:06:21","modified_gmt":"2026-04-14T18:06:21","slug":"mc1279829-the-april-2026-windows-security-update-is-now-available","status":"publish","type":"post","link":"https:\/\/m365jp.net\/index.php\/2026-04-15-mc1279829-the-april-2026-windows-security-update-is-now-available","title":{"rendered":"MC1279829 | The April 2026 Windows security update is now available"},"content":{"rendered":"<div class=\"postie-post\">\n<div>\n<hr>\n<table id=\"section\">\n<tbody>\n<tr>\n<th width=\"95%\">MC1279829 | The April 2026 Windows security update is now available<\/th>\n<\/tr>\n<\/tbody>\n<\/table>\n<hr>\n<table id=\"data\">\n<tbody>\n<tr>\n<th>Classification<\/th>\n<td>stayInformed<\/td>\n<\/tr>\n<tr>\n<th>Last Updated<\/th>\n<td>04\/14\/2026 17:03:34<\/td>\n<\/tr>\n<tr>\n<th>Start Time<\/th>\n<td>04\/14\/2026 17:03:33<\/td>\n<\/tr>\n<tr>\n<th>End Time<\/th>\n<td>04\/14\/2027 17:03:33<\/td>\n<\/tr>\n<tr>\n<th>Message Content<\/th>\n<td>\n<div>The April 2026 security update is now available for all supported versions of Windows. We recommend that you install these updates promptly. For more information about the contents of this update, see the release notes, which are easily accessible from   the&nbsp;<a href=\"https:\/\/support.microsoft.com\/help\/5083769\" rel=\"noopener noreferrer\" target=\"_blank\">Windows 11<\/a> update history page. To learn more about the different types of monthly quality updates, see  <a href=\"https:\/\/aka.ms\/Windows\/MonthlyUpdates\" rel=\"noopener noreferrer\" target=\"_blank\">  Windows monthly updates explained<\/a>.<\/div>\n<div>&nbsp;&nbsp;<\/div>\n<div><b>Highlights for the Windows 11, version 25H2 update:&nbsp;<\/b><\/div>\n<ul>\n<li>This security update includes fixes and quality improvements from <a href=\"https:\/\/support.microsoft.com\/help\/5079391\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5079391<\/a> (released March 26, 2026 &#8211; no longer offered) and <a href=\"https:\/\/support.microsoft.com\/help\/5086672\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5086672<\/a> (released March 31, 2026).<\/li>\n<li>This update makes quality improvements to the servicing stack, which is the component that installs Windows updates.<\/li>\n<li>This update expands high confidence device targeting data, increasing coverage of devices eligible to automatically receive new Secure Boot certificates. Devices receive the new certificates only after demonstrating sufficient successful update signals,   maintaining a controlled and phased rollout.<\/li>\n<li>This update improves reliability for SMB compression over QUIC, reducing timeouts and enabling more consistent and dependable performance.<\/li>\n<li>This update enhances protection against phishing attacks that use Remote Desktop (.rdp) files by showing all requested connection settings before connecting, with settings turned off by default and a  <a href=\"https:\/\/go.microsoft.com\/fwlink\/?linkid=2347342\" rel=\"noopener noreferrer\" target=\"_blank\">  one\u2011time security warning<\/a> on first use.<\/li>\n<\/ul>\n<div>  <\/div>\n<div>Short on time? Watch our <a href=\"https:\/\/aka.ms\/Windows11\/ReleaseNotes\/Video\/2604\" rel=\"noopener noreferrer\" target=\"_blank\">  Windows 11 release notes video<\/a> for this month&#8217;s tips.<\/div>\n<div>  <\/div>\n<div>For instructions on how to install this update, see the KB for your operating system listed below:&nbsp;<\/div>\n<ul>\n<li>Windows 11, version 26H1: <a href=\"https:\/\/support.microsoft.com\/help\/5083768\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5083768<\/a><\/li>\n<li>Windows 11, versions 25H2 and 24H2: <a href=\"https:\/\/support.microsoft.com\/help\/5083769\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5083769<\/a><\/li>\n<li>Windows 11, version 23H2: <a href=\"https:\/\/support.microsoft.com\/help\/5082052\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082052<\/a><\/li>\n<li>Windows 11 Enterprise LTSC 2024: Baseline <a href=\"https:\/\/support.microsoft.com\/topic\/9df553dc-e869-4240-af42-c7bc7e81bc32\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5083769<\/a><\/li>\n<li>Windows 10, versions 22H2 and 21H2: <a href=\"https:\/\/support.microsoft.com\/help\/5082200\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082200<\/a><\/li>\n<li>Windows 10 Enterprise LTSC 2019 and Windows Server 2019: <a href=\"https:\/\/support.microsoft.com\/help\/5082123\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082123<\/a><\/li>\n<li>Windows 10 LTSB 2016 and Windows Server 2016: <a href=\"https:\/\/support.microsoft.com\/help\/5082198\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082198<\/a><\/li>\n<li>Windows Server 2025: <a href=\"https:\/\/support.microsoft.com\/help\/5082063\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082063<\/a><\/li>\n<li>Windows Server 2025 Datacenter: Azure Edition: Baseline <a href=\"https:\/\/support.microsoft.com\/topic\/3ed94012-763a-4ebe-86f4-32b01390a11a\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082063<\/a><\/li>\n<li>Windows Server 2022: <a href=\"https:\/\/support.microsoft.com\/help\/5082142\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082142<\/a><\/li>\n<li>Windows Server 2022 Datacenter: Azure Edition: Baseline <a href=\"https:\/\/support.microsoft.com\/topic\/5d0db586-d5a5-4ba2-b3c8-a4536db17225\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082142<\/a><\/li>\n<li>Windows Server 2012 R2: <a href=\"https:\/\/support.microsoft.com\/help\/5082126\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082126<\/a><\/li>\n<li>Windows Server 2012: <a href=\"https:\/\/support.microsoft.com\/help\/5082127\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082127<\/a><\/li>\n<\/ul>\n<div>  <\/div>\n<div><b>Note: <\/b>With the April 2026 Windows security update and upcoming Windows updates over the next few months, a limited number of consumer and business devices may experience one additional restart during installation. This one\u2011time restart occurs after   a Secure Boot certificate update is applied as part of the <a href=\"https:\/\/support.microsoft.com\/topic\/windows-secure-boot-certificate-expiration-and-ca-updates-7ff40d33-95dc-4c3c-8725-a9b95457578e\" rel=\"noopener noreferrer\" target=\"_blank\">  Secure Boot update process<\/a>.<\/div>\n<\/td>\n<\/tr>\n<tr>\n<th>Machine Translation<\/th>\n<td>\n<div>2026\u5e744\u6708\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306f\u3001\u30b5\u30dd\u30fc\u30c8\u3055\u308c\u308b\u3059\u3079\u3066\u306eWindows\u30d0\u30fc\u30b8\u30e7\u30f3\u3067\u5229\u7528\u53ef\u80fd\u306b\u306a\u308a\u307e\u3057\u305f\u3002\u3053\u308c\u3089\u306e\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306f\u901f\u3084\u304b\u306b\u30a4\u30f3\u30b9\u30c8\u30fc\u30eb\u3059\u308b\u3053\u3068\u3092\u63a8\u5968\u3057\u307e\u3059\u3002\u3053\u306e\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306e\u5185\u5bb9\u306b\u3064\u3044\u3066\u306e\u8a73\u7d30\u306f\u3001<a href=\"https:\/\/support.microsoft.com\/help\/5083769\" rel=\"noopener noreferrer\" target=\"_blank\">Windows 11<\/a> \u306e\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u5c65\u6b74\u30da\u30fc\u30b8\u304b\u3089&nbsp;\u7c21\u5358\u306b\u30a2\u30af\u30bb\u30b9\u3067\u304d\u308b\u30ea\u30ea\u30fc\u30b9\u30ce\u30fc\u30c8\u3092\u3054\u89a7\u304f\u3060\u3055\u3044\u3002\u6708\u6b21\u54c1\u8cea\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306e\u7a2e\u985e\u306b\u3064\u3044\u3066\u8a73\u3057\u304f\u77e5\u308a\u305f\u3044\u65b9\u306f\u3001  <a href=\"https:\/\/aka.ms\/Windows\/MonthlyUpdates\" rel=\"noopener noreferrer\" target=\"_blank\">  Windows\u6708\u6b21\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306e\u8aac\u660e<\/a>\u3092\u3054\u89a7\u304f\u3060\u3055\u3044\u3002<\/div>\n<div>&nbsp;&nbsp;<\/div>\n<div><b>Windows 11 \u30d0\u30fc\u30b8\u30e7\u30f325H2\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306e\u30cf\u30a4\u30e9\u30a4\u30c8:&nbsp;<\/b><\/div>\n<ul>\n<li>\u3053\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306b\u306f\u3001 <a href=\"https:\/\/support.microsoft.com\/help\/5079391\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5079391<\/a> (2026\u5e743\u670826\u65e5\u30ea\u30ea\u30fc\u30b9\u3001\u73fe\u5728\u306f\u63d0\u4f9b\u7d42\u4e86)\u304a\u3088\u3073 <a href=\"https:\/\/support.microsoft.com\/help\/5086672\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5086672<\/a> (2026\u5e743\u670831\u65e5\u30ea\u30ea\u30fc\u30b9)\u304b\u3089\u306e\u4fee\u6b63\u3068\u54c1\u8cea\u5411\u4e0a\u304c\u542b\u307e\u308c\u3066\u3044\u307e\u3059\u3002<\/li>\n<li>\u3053\u306e\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306f\u3001Windows\u306e\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u3092\u30a4\u30f3\u30b9\u30c8\u30fc\u30eb\u3059\u308b\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u3067\u3042\u308b\u30b5\u30fc\u30d3\u30b9\u30b9\u30bf\u30c3\u30af\u306e\u54c1\u8cea\u3092\u6539\u5584\u3057\u307e\u3059\u3002<\/li>\n<li>\u3053\u306e\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306f\u9ad8\u4fe1\u983c\u30c7\u30d0\u30a4\u30b9\u30bf\u30fc\u30b2\u30c6\u30a3\u30f3\u30b0\u30c7\u30fc\u30bf\u3092\u62e1\u5145\u3057\u3001\u65b0\u305f\u306a\u30bb\u30ad\u30e5\u30a2\u30d6\u30fc\u30c8\u8a3c\u660e\u66f8\u3092\u81ea\u52d5\u7684\u306b\u53d7\u3051\u53d6\u308b\u5bfe\u8c61\u30c7\u30d0\u30a4\u30b9\u306e\u30ab\u30d0\u30fc\u7bc4\u56f2\u3092\u62e1\u5927\u3057\u307e\u3059\u3002\u30c7\u30d0\u30a4\u30b9\u306f\u3001\u5341\u5206\u306a\u6210\u529f\u3057\u305f\u66f4\u65b0\u4fe1\u53f7\u3092\u793a\u3057\u3001\u5236\u5fa1\u3055\u308c\u305f\u6bb5\u968e\u7684\u306a\u5c55\u958b\u3092\u7dad\u6301\u3057\u305f\u5f8c\u306b\u306e\u307f\u65b0\u3057\u3044\u8a3c\u660e\u66f8\u3092\u53d7\u3051\u53d6\u308a\u307e\u3059\u3002<\/li>\n<li>\u3053\u306e\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306b\u3088\u308a\u3001SMB\u5727\u7e2e\u306e\u4fe1\u983c\u6027\u304c\u5411\u4e0a\u3057\u3001\u30bf\u30a4\u30e0\u30a2\u30a6\u30c8\u3092\u6e1b\u3089\u3057\u3001\u3088\u308a\u4e00\u8cab\u6027\u306e\u3042\u308b\u4fe1\u983c\u6027\u306e\u9ad8\u3044\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u5b9f\u73fe\u3057\u307e\u3059\u3002<\/li>\n<li>\u3053\u306e\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u3067\u306f\u3001\u30ea\u30e2\u30fc\u30c8\u30c7\u30b9\u30af\u30c8\u30c3\u30d7(.rdp)\u30d5\u30a1\u30a4\u30eb\u3092\u5229\u7528\u3059\u308b\u30d5\u30a3\u30c3\u30b7\u30f3\u30b0\u653b\u6483\u306b\u5bfe\u3059\u308b\u4fdd\u8b77\u3092\u5f37\u5316\u3057\u3001\u63a5\u7d9a\u524d\u306b\u8981\u6c42\u3055\u308c\u305f\u3059\u3079\u3066\u306e\u63a5\u7d9a\u8a2d\u5b9a\u304c\u8868\u793a\u3055\u308c\u3001\u8a2d\u5b9a\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u3067\u30aa\u30d5\u306b\u3057\u3001\u521d\u56de\u4f7f\u7528\u6642\u306b\u306f  <a href=\"https:\/\/go.microsoft.com\/fwlink\/?linkid=2347342\" rel=\"noopener noreferrer\" target=\"_blank\">  \u4e00\u5ea6\u3060\u3051\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u8b66\u544a<\/a> \u304c\u8868\u793a\u3055\u308c\u307e\u3059\u3002<\/li>\n<\/ul>\n<div>  <\/div>\n<div>\u6642\u9593\u304c\u306a\u3044?\u4eca\u6708\u306e\u30d2\u30f3\u30c8\u306f <a href=\"https:\/\/aka.ms\/Windows11\/ReleaseNotes\/Video\/2604\" rel=\"noopener noreferrer\" target=\"_blank\">  Windows 11\u30ea\u30ea\u30fc\u30b9\u30ce\u30fc\u30c8\u306e\u52d5\u753b<\/a> \u3092\u3054\u89a7\u304f\u3060\u3055\u3044\u3002<\/div>\n<div>  <\/div>\n<div>\u3053\u306e\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306e\u30a4\u30f3\u30b9\u30c8\u30fc\u30eb\u65b9\u6cd5\u306b\u3064\u3044\u3066\u306f\u3001\u4ee5\u4e0b\u306e\u30aa\u30da\u30ec\u30fc\u30c6\u30a3\u30f3\u30b0\u30b7\u30b9\u30c6\u30e0\u306e\u77e5\u8b58\u5eab(KB)\u3092\u3054\u89a7\u304f\u3060\u3055\u3044\u3002&nbsp;<\/div>\n<ul>\n<li>Windows 11\u3001\u30d0\u30fc\u30b8\u30e7\u30f326H1: <a href=\"https:\/\/support.microsoft.com\/help\/5083768\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5083768<\/a><\/li>\n<li>Windows 11\u3001\u30d0\u30fc\u30b8\u30e7\u30f325H2\u304a\u3088\u307324H2: <a href=\"https:\/\/support.microsoft.com\/help\/5083769\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5083769<\/a><\/li>\n<li>Windows 11\u3001\u30d0\u30fc\u30b8\u30e7\u30f323H2: <a href=\"https:\/\/support.microsoft.com\/help\/5082052\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082052<\/a><\/li>\n<li>Windows 11 Enterprise LTSC 2024:\u30d9\u30fc\u30b9\u30e9\u30a4\u30f3 <a href=\"https:\/\/support.microsoft.com\/topic\/9df553dc-e869-4240-af42-c7bc7e81bc32\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5083769<\/a><\/li>\n<li>Windows 10\u3001\u30d0\u30fc\u30b8\u30e7\u30f322H2\u304a\u3088\u307321H2: <a href=\"https:\/\/support.microsoft.com\/help\/5082200\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082200<\/a><\/li>\n<li>Windows 10 Enterprise LTSC 2019\u304a\u3088\u3073Windows Server 2019: <a href=\"https:\/\/support.microsoft.com\/help\/5082123\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082123<\/a><\/li>\n<li>Windows 10 LTSB 2016\u304a\u3088\u3073Windows Server 2016: <a href=\"https:\/\/support.microsoft.com\/help\/5082198\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082198<\/a><\/li>\n<li>Windows Server 2025: <a href=\"https:\/\/support.microsoft.com\/help\/5082063\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082063<\/a><\/li>\n<li>Windows Server 2025 Datacenter: Azure Edition: Baseline <a href=\"https:\/\/support.microsoft.com\/topic\/3ed94012-763a-4ebe-86f4-32b01390a11a\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082063<\/a><\/li>\n<li>Windows Server 2022: <a href=\"https:\/\/support.microsoft.com\/help\/5082142\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082142<\/a><\/li>\n<li>Windows Server 2022 Datacenter: Azure Edition: Baseline <a href=\"https:\/\/support.microsoft.com\/topic\/5d0db586-d5a5-4ba2-b3c8-a4536db17225\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082142<\/a><\/li>\n<li>Windows Server 2012 R2: <a href=\"https:\/\/support.microsoft.com\/help\/5082126\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082126<\/a><\/li>\n<li>Windows Server 2012: <a href=\"https:\/\/support.microsoft.com\/help\/5082127\" rel=\"noopener noreferrer\" target=\"_blank\">  KB5082127<\/a><\/li>\n<\/ul>\n<div>  <\/div>\n<div><b>\u6ce8: <\/b>2026\u5e744\u6708\u306eWindows\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u304a\u3088\u3073\u4eca\u5f8c\u6570\u304b\u6708\u306eWindows\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u306b\u3088\u308a\u3001\u9650\u3089\u308c\u305f\u6570\u306e\u6d88\u8cbb\u8005\u304a\u3088\u3073\u30d3\u30b8\u30cd\u30b9\u30c7\u30d0\u30a4\u30b9\u304c\u30a4\u30f3\u30b9\u30c8\u30fc\u30eb\u6642\u306b\u3055\u3089\u306b1\u56de\u518d\u8d77\u52d5\u3055\u308c\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u306e\u4e00\u5ea6\u304d\u308a\u306e\u518d\u8d77\u52d5\u306f\u3001\u30bb\u30ad\u30e5\u30a2\u30d6\u30fc\u30c8\u8a3c\u660e\u66f8\u306e\u66f4\u65b0\u304c\u30bb  <a href=\"https:\/\/support.microsoft.com\/topic\/windows-secure-boot-certificate-expiration-and-ca-updates-7ff40d33-95dc-4c3c-8725-a9b95457578e\" rel=\"noopener noreferrer\" target=\"_blank\">  \u30ad\u30e5\u30a2\u30d6\u30fc\u30c8\u306e\u66f4\u65b0\u30d7\u30ed\u30bb\u30b9<\/a>\u306e\u4e00\u90e8\u3068\u3057\u3066\u9069\u7528\u3055\u308c\u305f\u5f8c\u306b\u884c\u308f\u308c\u307e\u3059\u3002<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>MC1279829 | The April 2026 Windows security update is now available Classification stayInformed Last Updated 0 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-15912","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/15912","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/comments?post=15912"}],"version-history":[{"count":0,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/15912\/revisions"}],"wp:attachment":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/media?parent=15912"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/categories?post=15912"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/tags?post=15912"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}