COMMON WEAKNESS ENUMERATIONDraft

CWE-1312

Missing Protection for Mirrored Regions in On-Chip Fabric Firewall

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.

Abstraction

Base

Structure

Simple

Likelihood of Exploit

Medium

Understand the problem

What is the problem?

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.

Extended description

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.

Root cause

How and when does the problem arise?

Lifecycle phase

Architecture and Design

Lifecycle phase

Implementation

Risk

What does successful exploitation lead to?

Modify MemoryRead MemoryBypass Protection Mechanism

Affected security scopes: Confidentiality, Integrity, Access Control

Defence

How is it prevented and fixed?

Architecture and Design

Architecture and design approach

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

Implementation

Implementation-phase defence

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

Verification

How is it detected?

Manual Dynamic Analysis

High
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.
CWE-1312: Common Weakness Enumeration Entry CWE-1312 · DayBreach Sözlük · DayBreach