Windows Storage CVE-2026-100225

Exploitation requires the attacker to already possess local, authenticated access with at least low privileges on the target Windows host (PR:L, AV:L) - this is a post-compromise escalation, not a remote or unauthenticated vector. The flaw is in the Windows Storage component; no user interaction is needed (UI:N). The key limiting factor is the High attack complexity (AC:H): reliable exploitation of this heap-based buffer overflow (CWE-122) depends on controlling heap layout/allocation state or winning a race, so success is not deterministic and defenders can treat it as a second-stage privilege-escalation primitive rather than an easy or widespread attack.

This is a moderate-priority local privilege escalation, not a drop-everything emergency. The CVSS 3.1 vector (AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H, base 7.0) tells a consistent story: the attacker must already have local, authenticated low-privileged code execution (AV:L, PR:L), and exploitation is non-trivial (AC:H) because reliably grooming and corrupting the heap in Windows Storage typically requires winning a race or controlling specific allocation state. The payoff is high - full confidentiality, integrity, and availability impact (C:H/I:H/A:H), consistent with escalation to SYSTEM. No EPSS score, KEV listing, or POC indicator was provided in the input, so exploitation probability signals are absent rather than low. There is no conflict between the vector and the description: both agree on local, authorized access, so the 'authorized attacker ... locally' wording aligns with PR:L/AV:L. The main caveat is that AC:H and the need for pre-existing local access meaningfully reduce real-world risk versus a remote unauthenticated flaw of the same base score; treat this as a post-compromise escalation primitive (second-stage in an attack) rather than an initial-access or wormable threat. Patch prioritization should still be high given the ubiquity of Windows and the SYSTEM-level outcome.

An attacker who has already gained low-privileged code execution on a Windows host (e.g., via phishing, a standard user account, or a compromised service) triggers the heap-based buffer overflow in the Windows Storage component to corrupt kernel or privileged heap memory and elevate to SYSTEM. Because AC is High, the attacker likely must perform heap grooming or win a timing/race condition, so exploitation is not guaranteed on the first attempt. No public exploit identified at time of analysis.