The vulnerability is a stack‑based buffer overflow in the Windows Client‑Side Caching (CSC) Service. It enables an attacker who already has local authority on a machine to gain higher privileges by corrupting the stack and potentially executing arbitrary code. The weakness is classified as a classic out‑of‑bounds write identified as CWE‑121.

Affected products include various releases of Windows 10 from version 1607 to 22H2 and Windows 11 from 23H2 to 26H2, as well as Windows Server 2012 through Server 2025. The CSC Service is installed as part of the operating system in these versions, making the vulnerability present on a wide range of desktop, hybrid, and server deployments.

The CVSS score of 7.8 reflects a medium‑to‑high severity for local privilege escalation. The EPSS score is listed as < 1 %, indicating a very low but nonzero exploitation probability. The vulnerability is not listed in CISA’s KEV catalog, implying no proven remote exploitation in the wild as of now. Based on the description, it is inferred that the likely attack vector is a local user with sufficient authority to invoke CSC operations that trigger the overflow path.