The software incorrectly checks a return value from a function, which prevents the software from detecting errors or exceptional conditions.
Extended Description
Important and common functions will return some value about the success of its actions. This will alert the program whether or not to handle any errors caused by that function.
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
Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.
Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.
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 "Software Development" (CWE-699)
Nature
Type
ID
Name
MemberOf
Category - a CWE entry that contains a set of other entries that share a common characteristic.
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
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.
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
Availability Integrity
Technical Impact: Unexpected State; DoS: Crash, Exit, or Restart
An unexpected return value could place the system in a state that could lead to a crash or other unintended behaviors.
Likelihood Of Exploit
Low
Demonstrative Examples
Example 1
This code attempts to allocate memory for 4 integers and checks if the allocation succeeds.
(bad code)
Example Language: C
tmp = malloc(sizeof(int) * 4); if (tmp < 0 ) {
perror("Failure"); //should have checked if the call returned 0
}
The code assumes that only a negative return value would indicate an error, but malloc() may return a null pointer when there is an error. The value of tmp could then be equal to 0, and the error would be missed.
Potential Mitigations
Phase: Architecture and Design
Strategy: Language Selection
Use a language or compiler that uses exceptions and requires the catching of those exceptions.
Phase: Implementation
Properly check all functions which return a value.
Phase: Implementation
When designing any function make sure you return a value or throw an exception in case of an error.
Memberships
This MemberOf Relationships table shows additional CWE Categories and Views that reference this weakness as a member. This information is often useful in understanding where a weakness fits within the context of external information sources.
Nature
Type
ID
Name
MemberOf
View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).
[REF-62] Mark Dowd, John McDonald
and Justin Schuh. "The Art of Software Security Assessment". Chapter 7, "Return Value Testing and Interpretation", Page 340. 1st Edition. Addison Wesley. 2006.