CWE-781: Improper Address Validation in IOCTL with METHOD_NEITHER I/O Control Code
Weakness ID: 781
Abstraction: Variant Structure: Simple
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Description
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.
Relationships
This table shows the weaknesses and high level categories that are related to this weakness. These relationships are defined as ChildOf, ParentOf, MemberOf and give insight to similar items that may exist at higher and lower levels of abstraction. In addition, relationships such as PeerOf and CanAlsoBe are defined to show similar weaknesses that the user may want to explore.
Relevant to the view "Research Concepts" (CWE-1000)
Nature
Type
ID
Name
ChildOf
Base - a weakness
that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.
Variant - a weakness
that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.
Base - a weakness
that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.
The different Modes of Introduction provide information about how and when this weakness may be introduced. The Phase identifies a point in the life cycle at which introduction may occur, while the Note provides a typical scenario related to introduction during the given phase.
Phase
Note
Architecture and Design
Implementation
Applicable Platforms
This listing shows possible areas for which the given weakness could appear. These may be for specific named Languages, Operating Systems, Architectures, Paradigms, Technologies, or a class of such platforms. The platform is listed along with how frequently the given weakness appears for that instance.
Languages
C (Often Prevalent)
C++ (Often Prevalent)
Operating Systems
Windows NT (Sometimes Prevalent)
Common Consequences
This table specifies different individual consequences associated with the weakness. The Scope identifies the application security area that is violated, while the Impact describes the negative technical impact that arises if an adversary succeeds in exploiting this weakness. The Likelihood provides information about how likely the specific consequence is expected to be seen relative to the other consequences in the list. For example, there may be high likelihood that a weakness will be exploited to achieve a certain impact, but a low likelihood that it will be exploited to achieve a different impact.
Scope
Impact
Likelihood
Integrity Availability Confidentiality
Technical Impact: Modify Memory; Read Memory; Execute Unauthorized Code or Commands; DoS: Crash, Exit, or Restart
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.
chain: device driver for packet-capturing software allows access to an unintended IOCTL with resultant array index error.
Potential Mitigations
Phase: Implementation
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.
Phase: Architecture and Design
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.
Phases: Architecture and Design; Implementation
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.
Notes
Applicable Platform
Because IOCTL functionality is typically performing low-level actions and closely interacts with the operating system, this weakness may only appear in code that is written in low-level languages.
Research Gap
While this type of issue has been known since 2006, it is probably still under-studied and under-reported. Most of the focus has been on high-profile software and security products, but other kinds of system software also use drivers. Since exploitation requires the development of custom code, it requires some skill to find this weakness.
Because exploitation typically requires local privileges, it might not be a priority for active attackers. However, remote exploitation may be possible for software such as device drivers. Even when remote vectors are not available, it may be useful as the final privilege-escalation step in multi-stage remote attacks against application-layer software, or as the primary attack by a local user on a multi-user system.