CWE-456

Variant 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 Initialization of a Variable

Description

The product does not initialize critical variables, which causes the execution environment to use unexpected values.

Consequences

Integrity, Other — Unexpected State, Quality Degradation, Varies by Context

The uninitialized data may be invalid, causing logic errors within the program. In some cases, this could result in a security problem.

Mitigations

Phase: Implementation

Ensure that critical variables are initialized before first use [REF-1485].

Phase: Requirements

Choose a language that is not susceptible to these issues.

Detection

Automated Static Analysis

Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)