Windows HID Driver CVE-2026-69731

Exploitation requires an authenticated local session with at minimum a standard (low-privileged) Windows user account, as confirmed by the CVSS AV:L/PR:L vector. The HID class driver is loaded by default on all Windows installations that support Human Interface Devices - no special hardware beyond standard peripherals (or the ability to emulate HID traffic) is needed, and no non-default configuration is required. Limits on exploitation: the attacker must already possess local code execution on the target host (no remote unauthenticated path exists); privilege escalation is scoped to the local system (S:U, no lateral movement directly from this flaw alone). Windows Kernel Data Protection (KDP), Credential Guard, and hypervisor-protected code integrity may complicate certain post-exploitation techniques on modern systems but do not prevent the overflow or the initial privilege escalation itself.

The CVSS 7.8 vector (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) is well-calibrated: local access with a low-privileged account is required, but once achieved the overflow is low-complexity and requires no user interaction, yielding full system compromise. The AV:L constraint is the primary limiting factor, meaning the attacker must already have a foothold - typical via phishing, supply chain, or credential theft in an enterprise context. No EPSS score was provided, so exploitation probability cannot be quantified numerically; however, AC:L combined with ubiquitous Windows deployment makes this a high-priority patch for any organization facing insider threat or post-initial-access lateral movement scenarios. No KEV listing and no public POC code have been identified, suggesting exploitation remains in researcher or threat-actor toolkits rather than commodity exploit frameworks. Patch availability from Microsoft substantially reduces residual risk for maintained fleets.

A threat actor who has obtained a standard-user shell on a Windows endpoint - for example, via a phishing-delivered macro or harvested credentials - crafts an IOCTL or synthesizes a malformed HID device report that triggers the heap overflow in the kernel-mode HID class driver. The corrupted kernel heap allows overwriting a token pointer or security descriptor, elevating the attacker's process to SYSTEM privileges. No public exploit code has been identified at time of analysis, but AC:L indicates reliable triggering once the overflow offset and payload are established.