Description

In handle_le_monitor_device_event of msft.cc, there is a possible control-flow hijack in the privileged bluetooth process due to an uninitialized pointer dereference. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-10-05T19:17:20.983Z",
  "pubdate": "2026-10-05T19:17:20.983Z",
  "executiveSummary": "A critical vulnerability has been identified within the Bluetooth subsystem, specifically located in the handle_le_monitor_device_event function within msft.cc. The flaw involves an uninitialized pointer dereference, which introduces a significant risk of control-flow hijacking within the privileged bluetooth process.\nThis vulnerability poses a severe threat to system security as it enables local escalation of privilege (LPE). The exploit does not require any additional execution privileges, nor does it necessitate user interaction, making it a highly dangerous zero-click local attack vector.\nThe privileged nature of the process hosting the vulnerability means that successful exploitation could grant an attacker elevated system access, potentially bypassing critical OS-level security boundaries. Given the lack of required interaction and the nature of the Bluetooth stack, the attack surface is exposed to any local actor capable of triggering Bluetooth LE monitoring events.\nThe risk profile is high, as the vulnerability affects the fundamental integrity of the Bluetooth process, allowing for arbitrary code execution in a context that may have broader system permissions.",
  "technicalDetails": "The vulnerability originates in the handle_le_monitor_device_event function residing in the msft.cc source file. The root cause is an uninitialized pointer that is subsequently dereferenced during the processing of Bluetooth Low Energy (LE) monitor device events.\nIn C++ and similar languages, failing to initialize a pointer results in the variable containing an indeterminate memory address. When the program logic reaches a point where it attempts to access the data at that pointer address, the execution flow is redirected to an attacker-controlled or otherwise invalid memory location. If an attacker can influence the memory state prior to this dereference—for example, via heap spraying or manipulating the heap layout—they may cause the process to execute arbitrary code.\nThe attack flow proceeds as follows: First, the attacker triggers an LE monitor device event, which is handled by the compromised function. Second, due to the missing initialization, the system attempts to perform an operation on the uninitialized memory. Third, by controlling the contents of the memory at the address being dereferenced, the attacker can overwrite function pointers or return addresses stored in the stack or heap.\nThis control-flow hijack effectively redirects the instruction pointer to a payload provided by the attacker, executing it with the privileges of the bluetooth process. Because this process typically runs with elevated system privileges, the transition from an unprivileged local state to a high-privileged state is immediate. The exploitation does not require the attacker to have pre-existing privileges beyond the ability to communicate with the Bluetooth stack, and no user action is required to trigger the event processing logic.\nThe impact of this vulnerability is total system compromise from a local perspective. By executing malicious code within the context of the Bluetooth process, an attacker can bypass hardware and software sandboxing mechanisms, intercept sensitive Bluetooth communications, or establish persistence within the operating system kernel or privileged user-space services. The lack of memory safety checks in the pointer dereference path facilitates this arbitrary code execution, rendering traditional boundary protections insufficient if the attacker can map their payload successfully in memory."
}