CWE-1290

Incorrect Decoding of Security Identifiers
AI Translation Available

The product implements a decoding mechanism to decode certain bus-transaction signals to security identifiers. If the decoding is implemented incorrectly, then untrusted agents can now gain unauthorized access to the asset.

Status
incomplete
Abstraction
base
Bus/Interface Hardware Not Technology-Specific

In a System-On-Chip (SoC), various integrated circuits and hardware engines generate transactions such as to access (reads/writes) assets or perform certain actions (e.g., reset, fetch, compute, etc.). Among various types of message information, a typical transaction is comprised of source identity (to identify the originator of the transaction) and a destination identity (to route the transaction to the respective entity). Sometimes the transactions are qualified with a security identifier. The security identifier helps the destination agent decide on the set of allowed actions (e.g., access an asset for read and writes). A decoder decodes the bus transactions to map security identifiers into necessary access-controls/protections.

A common weakness that can exist in this scenario is incorrect decoding because an untrusted agent's security identifier is decoded into a trusted agent's security identifier. Thus, an untrusted agent previously without access to an asset can now gain access to the asset.

Common Consequences

confidentiality integrity availability access control
Impacts
modify memory read memory dos: resource consumption (other) execute unauthorized code or commands gain privileges or assume identity quality degradation

Potential Mitigations

Phases:
architecture and design implementation
Descriptions:
• Access and programming flows must be tested in pre-silicon and post-silicon testing in order to check for this weakness.
• Security identifier decoders must be reviewed for design consistency and common weaknesses.