CWE-1312

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 Draft 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
Missing Protection for Mirrored Regions in On-Chip Fabric Firewall

Description

The firewall in an on-chip fabric protects the main addressed region, but it does not protect any mirrored memory or memory-mapped-IO (MMIO) regions.

Few fabrics mirror memory and address ranges, where mirrored regions contain copies of the original data. This redundancy is used to achieve fault tolerance. Whatever protections the fabric firewall implements for the original region should also apply to the mirrored regions. If not, an attacker could bypass existing read/write protections by reading from/writing to the mirrored regions to leak or corrupt the original data.

Consequences

Confidentiality, Integrity, Access Control — Modify Memory, Read Memory, Bypass Protection Mechanism

Mitigations

Phase: Architecture and Design

The fabric firewall should apply the same protections as the original region to the mirrored regions.

Phase: Implementation

The fabric firewall should apply the same protections as the original region to the mirrored regions.

Detection

Manual Dynamic Analysis

Using an external debugger, send write transactions to mirrored regions to test if original, write-protected regions are modified. Similarly, send read transactions to mirrored regions to test if the original, read-protected signals can be read.