CVE-2021-37605 in MiWi
Summary
by MITRE • 08/05/2021
In the Microchip MiWi v6.5 software stack, there is a possibility of frame counters being being validated / updated prior to message authentication.
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Analysis
by VulDB Data Team • 08/10/2021
The vulnerability identified as CVE-2021-37605 resides within Microchip's MiWi v6.5 software stack, a widely deployed wireless communication framework used in IoT and embedded systems applications. This security flaw represents a critical issue in the cryptographic message authentication process that could compromise the integrity and authenticity of wireless communications. The vulnerability specifically affects the order of operations during frame counter validation and message authentication procedures, creating a window where frame counters are processed before proper message authentication occurs.
The technical flaw manifests as a race condition or improper sequence in the cryptographic validation workflow where the system validates frame counters before performing message authentication checks. This chronological misalignment creates a potential attack vector where malicious actors could manipulate frame counter values to bypass authentication mechanisms. The frame counter validation typically serves to prevent replay attacks by ensuring message sequence integrity, but when executed before authentication, it allows adversaries to exploit the temporal gap between counter validation and actual message verification. This vulnerability falls under the category of improper order of operations within cryptographic protocols, which is classified as CWE-1278 in the CWE database.
The operational impact of this vulnerability extends significantly across various IoT deployments that utilize Microchip's MiWi stack, particularly in industrial control systems, smart metering applications, and wireless sensor networks. Attackers could potentially exploit this weakness to inject malicious messages into authenticated communication channels, leading to unauthorized system modifications, data manipulation, or complete system compromise. The vulnerability undermines the fundamental security guarantees of the wireless communication protocol, as it allows for authenticated message injection attacks that could go undetected by the system's normal security monitoring mechanisms. This weakness particularly affects environments where security is paramount, such as smart grid infrastructure, building automation systems, and industrial IoT deployments where unauthorized access could result in significant operational disruptions or safety hazards.
Mitigation strategies for CVE-2021-37605 require immediate attention from system administrators and security teams responsible for maintaining IoT infrastructure. The primary recommendation involves upgrading to a patched version of the Microchip MiWi software stack that corrects the frame counter validation sequence to occur after message authentication. Organizations should conduct comprehensive vulnerability assessments to identify all systems utilizing the affected software stack and implement proper network monitoring to detect potential exploitation attempts. Security controls should include network segmentation to limit the attack surface, implementation of additional authentication layers, and regular security audits of wireless communication protocols. From an ATT&CK framework perspective, this vulnerability aligns with techniques involving credential access and privilege escalation, as it enables attackers to bypass authentication mechanisms and potentially gain unauthorized system access. System hardening measures should also include enabling secure configuration practices for wireless devices, implementing robust network access controls, and maintaining updated security patches across all networked devices to prevent exploitation of similar vulnerabilities in the broader IoT ecosystem.