CVE-2021-40342 in UNEM R16A
Summary
by MITRE • 01/06/2023
In the DES implementation, the affected product versions use a default key for encryption. Successful exploitation allows an attacker to obtain sensitive information and gain access to the network elements that are managed by the affected products versions. This issue affects * FOXMAN-UN product: FOXMAN-UN R16A, FOXMAN-UN R15B, FOXMAN-UN R15A, FOXMAN-UN R14B, FOXMAN-UN R14A, FOXMAN-UN R11B, FOXMAN-UN R11A, FOXMAN-UN R10C, FOXMAN-UN R9C; * UNEM product: UNEM R16A, UNEM R15B, UNEM R15A, UNEM R14B, UNEM R14A, UNEM R11B, UNEM R11A, UNEM R10C, UNEM R9C. List of CPEs: * cpe:2.3:a:hitachienergy:foxman-un:R16A:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:foxman-un:R15B:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:foxman-un:R15A:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:foxman-un:R14B:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:foxman-un:R14A:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:foxman-un:R11B:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:foxman-un:R11A:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:foxman-un:R10C:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:foxman-un:R9C:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:unem:R16A:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:unem:R15B:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:unem:R15A:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:unem:R14B:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:unem:R14A:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:unem:R11B:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:unem:R11A:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:unem:R10C:*:*:*:*:*:*:* * cpe:2.3:a:hitachienergy:unem:R9C:*:*:*:*:*:*:*
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Analysis
by VulDB Data Team • 01/29/2023
The vulnerability identified as CVE-2021-40342 represents a critical weakness in the cryptographic implementation of certain Hitachi Energy network management products including the FOXMAN-UN and UNEM series. This flaw specifically targets the Data Encryption Standard (DES) algorithm implementation where the affected devices utilize a default cryptographic key for encryption operations rather than employing unique, securely generated keys. The use of default keys creates a significant security risk as these keys are widely known and can be easily obtained through reverse engineering or public documentation, fundamentally undermining the confidentiality protections that encryption is designed to provide.
The technical nature of this vulnerability stems from poor cryptographic key management practices within the embedded systems. When devices rely on default keys instead of generating unique cryptographic material for each instance, they become vulnerable to what is classified as a weak key vulnerability under CWE-327, which specifically addresses the use of weak or predictable cryptographic keys. This weakness allows attackers to perform decryption operations without proper authorization, enabling them to access sensitive information that should remain protected. The vulnerability is particularly concerning because it affects network management elements that control critical infrastructure components, making it a prime target for adversaries seeking unauthorized access to operational technology environments.
The operational impact of this vulnerability extends beyond simple information disclosure to encompass full network access and potential system compromise. Attackers who successfully exploit this weakness can gain unauthorized access to network elements managed by the affected products, potentially leading to complete system control and the ability to manipulate network configurations. This represents a significant threat to industrial control systems where these devices are deployed, as it could enable attackers to disrupt operations, access confidential data, or even cause physical damage to infrastructure. The vulnerability affects multiple product generations across both the FOXMAN-UN and UNEM product lines, indicating a systemic issue within the cryptographic implementation approach used by Hitachi Energy.
Security mitigation strategies for this vulnerability must address both immediate remediation and long-term architectural improvements. Organizations should immediately update affected devices to the latest firmware versions provided by Hitachi Energy that implement proper cryptographic key generation and management. The vulnerability also highlights the importance of following security best practices such as those outlined in the NIST SP 800-57 standard for cryptographic key management, which emphasizes the need for unique, securely generated keys for each cryptographic operation. Additionally, network segmentation and access controls should be implemented to limit the potential impact of successful exploitation, as recommended by MITRE ATT&CK framework's techniques for credential access and lateral movement. Regular cryptographic audits and security assessments should be conducted to identify similar weaknesses in other embedded systems and ensure proper implementation of cryptographic standards across all network infrastructure components.