CVE-2019-16129 in CryptoAuthentication Library CryptoAuthLib
Summary
by MITRE • 10/23/2020
Microchip CryptoAuthentication Library CryptoAuthLib prior to 20191122 has a Buffer Overflow (issue 2 of 2).
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Analysis
by VulDB Data Team • 11/26/2020
The vulnerability identified as CVE-2019-16129 represents a critical buffer overflow flaw within Microchip's CryptoAuthentication Library known as CryptoAuthLib. This library serves as a fundamental component for cryptographic operations in various embedded systems and IoT devices, providing secure authentication and key management capabilities. The issue manifests specifically in versions prior to the 20191122 release, indicating that the vulnerability has been present for an extended period within the product lineage. The buffer overflow condition occurs as part of the library's operational functions, potentially affecting any system that relies on CryptoAuthLib for cryptographic authentication processes. This flaw constitutes a serious security weakness that could compromise the integrity and confidentiality of cryptographic operations within affected systems.
The technical implementation of this buffer overflow vulnerability stems from inadequate input validation and memory management within the CryptoAuthLib library. When processing certain cryptographic commands or data structures, the library fails to properly bounds-check buffer allocations, allowing maliciously crafted inputs to overwrite adjacent memory locations. This type of vulnerability falls under the Common Weakness Enumeration category CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking permits data to overwrite adjacent memory. The flaw likely occurs during the handling of authentication tokens, cryptographic key operations, or certificate processing functions where the library expects specific data formats but does not adequately validate the length or content of incoming data. The overflow can potentially corrupt critical program variables, function return addresses, or other memory structures essential for proper library operation.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as it creates opportunities for privilege escalation and arbitrary code execution within systems utilizing the affected library. Attackers who can influence the cryptographic operations performed by CryptoAuthLib may exploit this buffer overflow to gain unauthorized access to secure elements, potentially compromising the entire cryptographic infrastructure of affected devices. This vulnerability particularly affects embedded systems, IoT devices, and industrial control systems that rely on Microchip's authentication chips such as the ATECC508A and ATECC608A series. The exploitation of this flaw could result in complete system compromise, data exfiltration, or the ability to bypass authentication mechanisms that are critical for maintaining security boundaries in connected environments. Organizations using these cryptographic libraries in production systems face significant risk of supply chain compromise and potential unauthorized access to sensitive data.
Mitigation strategies for CVE-2019-16129 primarily focus on immediate software updates and comprehensive system assessment. Organizations must upgrade to CryptoAuthLib version 20191122 or later, which contains the necessary patches to address the buffer overflow conditions. Additionally, system administrators should conduct thorough vulnerability assessments to identify all devices and applications that utilize the affected library. Implementing network segmentation and access controls can help limit the potential impact of exploitation attempts. The vulnerability also highlights the importance of secure coding practices and regular security audits in embedded systems development, particularly when dealing with cryptographic libraries that handle sensitive data. Security teams should monitor for potential exploitation attempts and implement intrusion detection systems to identify unusual patterns in cryptographic operations that might indicate attempted exploitation of this buffer overflow vulnerability. The remediation process should include comprehensive testing of updated libraries to ensure that the patch does not introduce regressions in functionality while maintaining the security improvements.