CVE-2026-83777

Summary

A heap-based buffer overflow in Windows Bluetooth Service allows unauthorized attackers on an adjacent network to elevate privileges, potentially gaining full control over affected systems. This vulnerability arises from improper bounds checking when handling Bluetooth data structures.

Exploitability

Exploitation requires an attacker to be on the same network segment as a target system, making it moderately difficult but achievable through network reconnaissance and packet injection techniques.

Blast radius

If exploited, this vulnerability could allow attackers to gain SYSTEM-level privileges on any Windows system running the Bluetooth service, potentially affecting entire corporate networks with multiple vulnerable devices.

Detection

Monitor for unusual Bluetooth service process behavior in Windows Event Logs, particularly Event ID 4624 (successful logon) and Event ID 4670 (permissions change) where elevated privileges appear without user interaction, and look for unexpected network traffic to Bluetooth service ports (typically TCP 1024-1025).

Prioritized remediation

Apply the latest Windows updates including KB5042819 or later, which contain the patched version of the Bluetooth service component that resolves this heap overflow vulnerability.

Analysis generated locally by garnet-coder (no data left the box). AI-assisted — verify against primary sources before acting.