An out‑of‑bounds read bug in the Spaceport.sys driver allows an authorized local attacker to read memory that should not be exposed. The vulnerability directly compromises confidentiality, potentially leaking sensitive operating system or user data from memory. The impact is confined to the system on which the attacker operates and requires the attacker to have sufficient privileges to load or interact with the vulnerable driver component.

Microsoft Windows 10 Build 1607, 1809, 21H2, 22H2 and Windows 11 Build 23H2, 24H2, 25H2, 26H1, and Windows Server 2016, 2019, 2022, 2025 – including Server Core installations – are affected. The issue is present across x86, x64, and ARM64 architectures as indicated by the Common Platform Enumeration strings.

The CVSS score is 5.5, classifying the vulnerability as moderately severe. The EPSS score is reported as <1%, indicating a very low but nonzero probability of exploitation, and the issue is not included in CISA’s KEV catalog. Exploitation requires a local user with authorization to load or interact with the Spaceport.sys driver; therefore the attack vector is inferred to be local. Because no active exploit exists in the public domain, the risk is primarily theoretical at this time but could become significant if later observed in zero‑day activity.