COMMON WEAKNESS ENUMERATIONDraft

CWE-572

Call to Thread run() instead of start()

The product calls a thread's run() method instead of calling start(), which causes the code to run in the thread of the caller instead of the callee.

Abstraction

Variant

Structure

Simple

Likelihood of Exploit

Medium

Understand the problem

What is the problem?

The product calls a thread's run() method instead of calling start(), which causes the code to run in the thread of the caller instead of the callee.

Extended description

In most cases a direct call to a Thread object's run() method is a bug. The programmer intended to begin a new thread of control, but accidentally called run() instead of start(), so the run() method will execute in the caller's thread of control.

Root cause

How and when does the problem arise?

Lifecycle phase

Implementation

Risk

What does successful exploitation lead to?

Quality DegradationVaries by Context

Affected security scopes: Other

Defence

How is it prevented and fixed?

Implementation

Implementation-phase defence

Detail
Use the start() method instead of the run() method.

Verification

How is it detected?

Automated Static Analysis

High
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.)