Weakness · High
CWE-1267: Policy Uses Obsolete Encoding
What it is
The product uses an obsolete encoding mechanism to implement access controls.
- Severity (our rating)
- High
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Architecture and Design, Implementation
- Exploited in the wild
- No CVE in CISA's catalog
In more detail
Within a System-On-a-Chip (SoC), various circuits and hardware engines generate transactions for the purpose of accessing (read/write) assets or performing various actions (e.g., reset, fetch, compute, etc.). Among various types of message information, a typical transaction is comprised of source identity (identifying the originator of the transaction) and a destination identity (routing the transaction to the respective entity). Sometimes the transactions are qualified with a Security Token. This Security Token helps the destination agent decide on the set of allowed actions (e.g., access to an asset for reads and writes). A policy encoder is used to map the bus transactions to Security Tokens that in turn are used as access-controls/protection mechanisms. A common weakness involves using an encoding which is no longer trusted, i.e., an obsolete encoding.
What an attacker can do
- Modify Memory (Confidentiality, Integrity, Availability, Access Control)
- Read Memory (Confidentiality, Integrity, Availability, Access Control)
- Modify Files or Directories (Confidentiality, Integrity, Availability, Access Control)
- Read Files or Directories (Confidentiality, Integrity, Availability, Access Control)
- DoS: Resource Consumption (Other) (Confidentiality, Integrity, Availability, Access Control)
- Execute Unauthorized Code or Commands (Confidentiality, Integrity, Availability, Access Control)
- Gain Privileges or Assume Identity (Confidentiality, Integrity, Availability, Access Control)
- Bypass Protection Mechanism (Confidentiality, Integrity, Availability, Access Control)
- Reduce Reliability (Confidentiality, Integrity, Availability, Access Control)
How to prevent it
Architecture and Design
- Security Token Decoders should be reviewed for design inconsistency and common weaknesses. Access and programming flows should be tested in both pre-silicon and post-silicon testing.
H2 Security
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.