CWE-1429—Missing Security-Relevant Feedback for Unexecuted Operations in Hardware Interface

Weakness Name

Missing Security-Relevant Feedback for Unexecuted Operations in Hardware Interface

Description

The product has a hardware interface that silently discards operations in situations for which feedback would be security-relevant, such as the timely detection of failures or attacks.

While some systems intentionally withhold feedback as a security measure, this approach must be strictly controlled to ensure it does not obscure operational failures that require prompt detection and remediation. Without these essential confirmations, failures go undetected, increasing the risk of data loss, security vulnerabilities, and overall system instability. Even when withholding feedback is an intentional part of a security policy designed, for example, to prevent attackers from gleaning sensitive internal details, the absence of expected feedback becomes a critical weakness when it masks operational failures that require prompt detection and remediation. For instance, certain encryption algorithms always return ciphertext regardless of errors to prevent attackers from gaining insight into internal state details. However, if such an algorithm fails to generate the expected ciphertext and provides no error feedback, the system cannot distinguish between a legitimate output and a malfunction. This can lead to undetected cryptographic failures, potentially compromising data security and system reliability. Without proper notification, a critical failure might remain hidden, undermining both the reliability and security of the process. Therefore, this weakness captures issues across various hardware interfaces where operations are discarded without any feedback, error handling, or logging. Such omissions can lead to data loss, security vulnerabilities, and system instability, with potential impacts ranging from minor to catastrophic. For some kinds of hardware products, some errors may be correctly identified and subsequently discarded, and the lack of feedback may have been an intentional design decision. However, this could result in a weakness if system operators or other authorized entities are not provided feedback about security-critical operations or failures that could prevent the operators from detecting and responding to an attack. For example:

Common Consequences

Scope:

Confidentiality

Impact:

Read Memory, Read Files or Directories

Notes:

Critical data may be exposed if operations are unexecuted or discarded silently, allowing attackers to exploit the lack of feedback.

Scope:

Integrity

Impact:

Modify Memory, Modify Files or Directories

Notes:

Operations may proceed based on incorrect assumptions, potentially causing data corruption or incorrect system behavior. In integrity-sensitive contexts, failing to signal that an operation did not occur as expected can mask errors that disrupt data consistency. Without feedback, the mitigation measures that should ensure updates have been performed cannot be verified, leaving the system vulnerable to both accidental and malicious data alterations.

Scope:

Availability

Impact:

DoS: Resource Consumption (Memory), DoS: Crash, Exit, or Restart

Notes:

Unhandled discarded operations can lead to resource exhaustion, triggering system crashes or denial of service. For availability, consistent feedback is crucial. Without proper notification of discarded operations, administrators or other authorized entities might miss early warning signs of resource imbalances. This delayed detection could allow a DoS condition to develop, compromising the system's ability to serve legitimate requests and maintain continuous operations.

Related Weaknesses

• CWE-223Omission of Security-relevant Information
• CWE-392Missing Report of Error Condition