CWE-1253

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
Incorrect Selection of Fuse Values

Description

The logic level used to set a system to a secure state relies on a fuse being unblown.

Fuses are often used to store secret data, including security configuration data. When not blown, a fuse is considered to store a logic 0, and, when blown, it indicates a logic 1. Fuses are generally considered to be one-directional, i.e., once blown to logic 1, it cannot be reset to logic 0.

Consequences

Access Control, Authorization — Bypass Protection Mechanism, Gain Privileges or Assume Identity

If the logic used to determine system-security state (by leveraging the values sensed from the fuses) uses negative logic, an attacker might blow the fuse and drive the system to an insecure state.

Availability — DoS: Crash, Exit, or Restart
Confidentiality — Read Memory
Integrity — Modify Memory, Execute Unauthorized Code or Commands

Mitigations

Phase: Architecture and Design

Logic should be designed in a way that blown fuses do not put the product into an insecure state that can be leveraged by an attacker.