CWE-1221

Base Abstraction Level
Pillar — Highest-level weakness category
Class — Abstract, language-independent
Base — Specific enough to detect
Variant — Tied to specific technology
Compound — Requires multiple weaknesses Incomplete MITRE CWE Status
Stable — Fully reviewed and complete
Draft — Under development, may change
Incomplete — Partially defined by MITRE
Deprecated — No longer recommended
Obsolete — Replaced by another CWE
Incorrect Register Defaults or Module Parameters

Description

Hardware description language code incorrectly defines register defaults or hardware Intellectual Property (IP) parameters to insecure values.

Integrated circuits and hardware IP software programmable controls and settings are commonly stored in register circuits. These register contents have to be initialized at hardware reset to defined default values that are hard coded in the hardware description language (HDL) code of the hardware unit. Hardware descriptive languages also support definition of parameter variables, which can be defined in code during instantiation of the hardware IP module. Such parameters are generally used to configure a specific instance of a hardware IP in the design. The system security settings of a hardware design can be affected by incorrectly defined default values or IP parameters. The hardware IP would be in an insecure state at power reset, and this can be exposed or exploited by untrusted software running on the system. Both register defaults and parameters are hardcoded values, which cannot be changed using software or firmware patches but must be changed in hardware silicon. Thus, such security issues are considerably more difficult to address later in the lifecycle. Hardware designs can have a large number of such parameters and register defaults settings, and it is important to have design tool support to check these settings in an automated way and be able to identify which settings are security sensitive.

Consequences

Confidentiality, Integrity, Availability, Access Control — Varies by Context

Degradation of system functionality, or loss of access control enforcement can occur.

Mitigations

Phase: Architecture and Design

During hardware design, all the system parameters and register defaults must be reviewed to identify security sensitive settings.

Phase: Implementation

The default values of these security sensitive settings need to be defined as part of the design review phase.

Detection

Automated Analysis

Use automated tools to test that values are configured per design specifications.