In the latest illustration of how quickly attackers can exploit newly disclosed flaws, Russia’s notorious APT28 cyber-espionage group has begun abusing a recently patched Microsoft vulnerability to steal emails and deploy malicious payloads against organizations in Central and Eastern Europe.<\/p>\n\n\n\n
CVE-2026-21509 is a security feature bypass vulnerability in Microsoft Office for which Microsoft rushed an out-of-cycle patch<\/a> on Jan. 26 after confirming active zero-day exploitation. The US Cybersecurity and Infrastructure Security Agency (CISA) added the flaw to its database of known exploited vulnerabilities at the time.<\/p>\n\n\nRussian Hackers Weaponize Microsoft Office Bug in Just 3 Days<\/a>: Russian Hackers Weaponize Microsoft Office Bug in Just 3 Days<\/span><\/a>","protected":false},"excerpt":{"rendered":" In the latest illustration of how quickly attackers can exploit newly disclosed flaws, Russia’s notorious APT28 cyber-espionage group has begun abusing a recently patched Microsoft vulnerability to steal emails and deploy malicious payloads against organizations in Central and Eastern Europe. CVE-2026-21509 is a security feature bypass vulnerability in Microsoft Office…<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20,17],"tags":[72,9],"class_list":["post-901","post","type-post","status-publish","format-standard","hentry","category-cybersecurity","category-vulnerability","tag-72","tag-russia"],"_links":{"self":[{"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/posts\/901","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/comments?post=901"}],"version-history":[{"count":1,"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/posts\/901\/revisions"}],"predecessor-version":[{"id":902,"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/posts\/901\/revisions\/902"}],"wp:attachment":[{"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/media?parent=901"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/categories?post=901"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/familiebuckens.nl\/index.php\/wp-json\/wp\/v2\/tags?post=901"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}