CVE-2023-4264 in Zephyr
Summary
by MITRE • 09/27/2023
Potential buffer overflow vulnerabilities n the Zephyr Bluetooth subsystem.
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Analysis
by VulDB Data Team • 10/20/2023
Buffer overflow vulnerabilities in the Zephyr Bluetooth subsystem represent critical security weaknesses that can compromise embedded IoT devices running this operating system. These vulnerabilities arise from insufficient input validation and improper memory management within the Bluetooth protocol stack implementation, creating opportunities for malicious actors to execute arbitrary code or cause denial of service conditions. The Zephyr project serves as a widely adopted real-time operating system for resource-constrained devices including smart sensors, wearables, and industrial IoT equipment where Bluetooth communication is prevalent.
The technical flaw manifests when the Bluetooth subsystem processes malformed or excessively large data packets without proper bounds checking mechanisms. Attackers can exploit these weaknesses by sending specially crafted Bluetooth advertisements, connection parameters, or data payloads that exceed allocated buffer sizes. This leads to memory corruption that can overwrite adjacent memory locations, potentially corrupting critical system structures, function pointers, or return addresses. The vulnerability is particularly dangerous in embedded environments where memory layout is deterministic and predictable, making exploitation more likely to succeed.
The operational impact of these buffer overflows extends beyond simple system crashes or restarts. Successful exploitation can enable attackers to gain full control over affected devices, allowing them to execute arbitrary code with the privileges of the Bluetooth stack process. This capability opens pathways for persistent backdoors, data exfiltration, and potential lateral movement within networked environments where multiple Zephyr-based devices exist. In industrial settings, such vulnerabilities could lead to production disruptions or safety hazards if critical control systems rely on these vulnerable Bluetooth implementations.
Mitigation strategies must address both immediate protection and long-term architectural improvements. Organizations should implement firmware updates from the Zephyr project maintainers as soon as patches become available, while also deploying network segmentation to limit exposure of vulnerable devices. Input validation controls should be strengthened at multiple layers including application-level checks and hardware-based memory protection mechanisms. The implementation of address space layout randomization and stack canaries can further complicate exploitation attempts. Security monitoring solutions should be deployed to detect anomalous Bluetooth traffic patterns that may indicate exploitation attempts, while regular security assessments of embedded device firmware should become standard practice.
These vulnerabilities align with CWE-121 Stack-based Buffer Overflow and CWE-122 Heap-based Buffer Overflow classifications, demonstrating the fundamental nature of memory safety issues in embedded systems. From an ATT&CK framework perspective, such weaknesses map to T1059 Command and Scripting Interpreter and T1068 Exploitation for Privilege Escalation tactics, as attackers leverage these flaws to gain elevated system privileges and execute malicious code within the device environment. The widespread adoption of Zephyr across various industries makes these vulnerabilities particularly concerning from a supply chain security standpoint, as compromising a single vulnerable device can potentially affect entire networks of interconnected IoT infrastructure.