CVE-2022-38028

CVE-2022-38028 is an elevation-of-privilege vulnerability (CVSS 3.1: 7.8) in the Microsoft Windows Print Spooler, the service that manages print jobs on Windows machines. An attacker who can already run low-privileged code on a vulnerable system can exploit the flaw locally, with no user interaction required, to escalate to SYSTEM privileges and take full control of the host (high confidentiality, integrity, and availability impact). It affects a broad set of Windows releases — Windows 10 builds 1507 through 21H2, Windows 11 22H2, Windows 8.1 and Windows RT 8.1, and Windows Server 2012, 2016, and 2019 — so most unpatched Windows estates are in scope. Exploitation is confirmed in the wild: CISA added the bug to the KEV catalog on 2024-04-23 (ransomware use unknown), and public reporting attributes active use to the Russia-linked APT28 group, whose custom 'GooseEgg' tool leverages this NSA-reported flaw to run payloads with elevated privileges; Microsoft shipped the fix in its April 2024 Patch Tuesday. EPSS is 14.9% (96th percentile), indicating elevated near-term exploitation risk on top of the already-observed APT28 activity.

What to do: Apply Microsoft's security updates for the affected Windows releases (fixed in the April 2024 Patch Tuesday); as a KEV entry, CISA requires applying vendor mitigations or discontinuing use of unpatched versions. On servers where printing is not required, disabling the Print Spooler service removes the local attack path. Given confirmed APT28 use of the 'GooseEgg' exploit, hunt for related activity on unpatched hosts and prioritize patching endpoints belonging to organizations and users targeted by APT28.