CVE-2016-5669 in DM-TXRX-100-STR
Summary
by MITRE
Crestron Electronics DM-TXRX-100-STR devices with firmware before 1.3039.00040 use a hardcoded X.509 certificate from an OpenSSL Test Certification Authority, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.
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Analysis
by VulDB Data Team • 11/02/2024
The CVE-2016-5669 vulnerability affects Crestron Electronics DM-TXRX-100-STR devices running firmware versions prior to 1.3039.00040, representing a critical security flaw that undermines the device's ability to establish secure communications. This vulnerability stems from the improper implementation of cryptographic security measures within the device's firmware, specifically through the inclusion of a hardcoded X.509 certificate issued by the OpenSSL Test Certification Authority. The presence of this test certificate indicates a development oversight where production devices were shipped with insecure default configurations rather than properly generated certificates for secure communications. This flaw fundamentally compromises the device's ability to authenticate legitimate servers and establish trusted connections, creating a significant attack surface for malicious actors seeking to exploit the system.
The technical nature of this vulnerability aligns with CWE-310, which addresses cryptographic weaknesses in authentication mechanisms, and specifically relates to improper certificate handling and the use of insecure default cryptographic parameters. The hardcoded certificate creates a persistent security risk because it remains unchanged across all affected devices, making it easily recognizable to attackers who can leverage this knowledge to craft malicious certificates that will be accepted by the vulnerable systems. This particular implementation flaw allows attackers to perform man-in-the-middle attacks by presenting forged certificates that match the hardcoded trust chain, effectively bypassing the device's security controls. The vulnerability operates at the transport layer security level, where the device's SSL/TLS implementation fails to properly validate certificate authenticity, enabling attackers to intercept and potentially modify communications between the device and its network endpoints.
The operational impact of this vulnerability extends beyond simple data interception, as it provides attackers with potential access to sensitive information transmitted through the device's network connections. The DM-TXRX-100-STR is typically used in professional audiovisual environments where secure transmission of control signals and configuration data is critical, making this vulnerability particularly dangerous in enterprise settings. Attackers could exploit this weakness to gain unauthorized access to device management interfaces, potentially leading to complete system compromise and unauthorized control of audiovisual equipment. The vulnerability also poses risks to network integrity, as compromised devices could serve as entry points for lateral movement within corporate networks, especially when these devices are connected to internal systems that handle sensitive data or critical infrastructure controls.
Organizations should immediately implement mitigations including firmware updates to version 1.3039.00040 or later, which addresses the hardcoded certificate issue by replacing it with properly generated certificates. Network segmentation and monitoring should be implemented to detect unauthorized certificate usage patterns, while security teams should conduct comprehensive inventories to identify all affected devices within their infrastructure. The vulnerability demonstrates the importance of proper certificate lifecycle management and adherence to security standards such as those outlined in the NIST SP 800-57 guidelines for cryptographic key management. Additionally, organizations should consider implementing certificate pinning mechanisms where appropriate to provide additional layers of protection against similar vulnerabilities, as this flaw represents a classic example of insufficient cryptographic implementation that can be addressed through proper security hardening practices and adherence to established security frameworks like those referenced in the MITRE ATT&CK framework for network security operations.