Cve 2026 21509

Russia's APT28 exploited CVE-2026-21509 to hit maritime and transport organizations across nine countries, with shipping firms making up 35% of targets.

Operation Neusploit saw Russia's APT28 exploit CVE-2026-21509 against 60+ Ukrainian targets within 72 hours of Microsoft's disclosure, delivering MiniDoor and BEARDSHELL backdoors.

CVE-2026-21509 bypasses OLE security protections across Office 2016-2024. CISA adds it to KEV catalog with February 16 deadline.