Description
The product uses physical debug or test
interfaces with support for multiple access levels, but it
assigns the wrong debug access level to an internal asset,
providing unintended access to the asset from untrusted debug
agents.
Modes of Introduction:
– Architecture and Design
Related Weaknesses
Consequences
Confidentiality: Read Memory
Integrity: Modify Memory
Authorization, Access Control: Gain Privileges or Assume Identity, Bypass Protection Mechanism
Potential Mitigations
Phase: Architecture and Design, Implementation
Effectiveness: High
Description:
Phase: Architecture and Design
Effectiveness: Limited
Description:
Apply blinding [REF-1219] or masking techniques in strategic areas.
Phase: Implementation
Effectiveness: Limited
Description:
Add shielding or tamper-resistant protections to the device, which increases the difficulty and cost for accessing debug/test interfaces.
CVE References
- CVE-2019-18827
- After ROM code execution, JTAG access is disabled. But before the ROM code is executed, JTAG access is possible, allowing a user full system access. This allows a user to modify the boot flow and successfully bypass the secure-boot process.