CWE-253

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 Incomplete 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 Exploit: Low
Incorrect Check of Function Return Value

Description

The product incorrectly checks a return value from a function, which prevents it from detecting errors or exceptional conditions.

Important and common functions will return some value about the success of its actions. This will alert the program whether or not to handle any errors caused by that function.

Consequences

Availability, Integrity — Unexpected State, DoS: Crash, Exit, or Restart

An unexpected return value could place the system in a state that could lead to a crash or other unintended behaviors.

Mitigations

Phase: Architecture and Design

Use a language or compiler that uses exceptions and requires the catching of those exceptions.

Phase: Implementation

Properly check all functions which return a value.

Phase: Implementation

When designing any function make sure you return a value or throw an exception in case of an error.

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.)