External Initialization of Trusted Variables or Data Stores

Opis

The product initializes critical internal variables or data stores using inputs that can be modified by untrusted actors.

A product system should be reluctant to trust variables that have been initialized outside of its trust boundary, especially if they are initialized by users. The variables may have been initialized incorrectly. If an attacker can initialize the variable, then they can influence what the vulnerable system will do.

Skutki

• Integrity

  Modify Application Data

  An attacker could gain access to and modify sensitive data or system information.

Zapobieganie

• Implementation · Input Validation

  A product system should be reluctant to trust variables that have been initialized outside of its trust boundary. Ensure adequate checking (e.g. input validation) is performed when relying on input from outside a trust boundary.

• Architecture and Design

  Avoid any external control of variables. If necessary, restrict the variables that can be modified using an allowlist, and use a different namespace or naming convention if possible.

Przykłady podatności

• CVE-2022-43468 WordPress module sets internal variables based on external inputs, allowing false reporting of the number of views
• CVE-2000-0959 Does not clear dangerous environment variables, enabling symlink attack.
• CVE-2001-0033 Specify alternate configuration directory in environment variable, enabling untrusted path.
• CVE-2001-0872 Dangerous environment variable not cleansed.
• CVE-2001-0084 Specify arbitrary modules using environment variable.

Słabość nadrzędna

• CWE-1419 Incorrect Initialization of Resource

Może też być

• CWE-456 Missing Initialization of a Variable

Kiedy powstaje

• Architecture and Design
• Implementation

Dotyczy

PHP, Not Language-Specific

Uwagi

Overlaps Missing variable initialization, especially in PHP.

This is often found in PHP due to register_globals and the common practice of storing library/include files under the web document root so that they are available using a direct request.