CWE-621—Variable Extraction Error

Weakness Name

Variable Extraction Error

Description

The product uses external input to determine the names of variables into which information is extracted, without verifying that the names of the specified variables are valid. This could cause the program to overwrite unintended variables.

For example, in PHP, extraction can be used to provide functionality similar to register_globals, a dangerous functionality that is frequently disabled in production systems. Calling extract() or import_request_variables() without the proper arguments could allow arbitrary global variables to be overwritten, including superglobals. Similar functionality is possible in other interpreted languages, including custom languages.

Common Consequences

Scope:

Integrity

Impact:

Modify Application Data

Notes:

An attacker could modify sensitive data or program variables.

Related Weaknesses

• CWE-471Modification of Assumed-Immutable Data (MAID)
• CWE-914Improper Control of Dynamically-Identified Variables