COMMON WEAKNESS ENUMERATIONDraft

CWE-781

Improper Address Validation in IOCTL with METHOD_NEITHER I/O Control Code

The product defines an IOCTL that uses METHOD_NEITHER for I/O, but it does not validate or incorrectly validates the addresses that are provided.

Abstraction

Variant

Structure

Simple

Likelihood of Exploit

Medium

Understand the problem

What is the problem?

The product defines an IOCTL that uses METHOD_NEITHER for I/O, but it does not validate or incorrectly validates the addresses that are provided.

Extended description

When an IOCTL uses the METHOD_NEITHER option for I/O control, it is the responsibility of the IOCTL to validate the addresses that have been supplied to it. If validation is missing or incorrect, attackers can supply arbitrary memory addresses, leading to code execution or a denial of service.

Root cause

How and when does the problem arise?

Lifecycle phase

Implementation

Risk

What does successful exploitation lead to?

Modify MemoryRead MemoryExecute Unauthorized Code or CommandsDoS: Crash, Exit, or Restart

Affected security scopes: Integrity, Availability, Confidentiality

An attacker may be able to access memory that belongs to another process or user. If the attacker can control the contents that the IOCTL writes, it may lead to code execution at high privilege levels. At the least, a crash can occur.

Defence

How is it prevented and fixed?

Implementation

Implementation-phase defence

Detail
If METHOD_NEITHER is required for the IOCTL, then ensure that all user-space addresses are properly validated before they are first accessed. The ProbeForRead and ProbeForWrite routines are available for this task. Also properly protect and manage the user-supplied buffers, since the I/O Manager does not do this when METHOD_NEITHER is being used. See References.

Architecture and Design

Architecture and design approach

Detail
If possible, avoid using METHOD_NEITHER in the IOCTL and select methods that effectively control the buffer size, such as METHOD_BUFFERED, METHOD_IN_DIRECT, or METHOD_OUT_DIRECT.

Architecture and Design · Implementation

Defence to apply across several lifecycle phases

Detail
If the IOCTL is part of a driver that is only intended to be accessed by trusted users, then use proper access control for the associated device or device namespace. See References.