The software has two different sources of the same data or information, but it uses the source that has less support for verification, is less trusted, or is less resistant to attack.
Relationships
The table(s) below 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.
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
The listings below show 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.
The table below 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
Access Control
Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity
An attacker could utilize the untrusted data source to bypass protection mechanisms and gain access to sensitive data.
Demonstrative Examples
Example 1
This code attempts to limit the access of a page to certain IP Addresses. It checks the 'HTTP_X_FORWARDED_FOR' header in case an authorized user is sending the request through a proxy.
(bad code)
Example Language: PHP
$requestingIP = '0.0.0.0'; if (array_key_exists('HTTP_X_FORWARDED_FOR', $_SERVER)) {
$requestingIP = $_SERVER['HTTP_X_FORWARDED_FOR'];
else{
$requestingIP = $_SERVER['REMOTE_ADDR'];
}
if(in_array($requestingIP,$ipAllowlist)){
generatePage(); return;
} else{
echo "You are not authorized to view this page"; return;
}
The 'HTTP_X_FORWARDED_FOR' header can be user controlled and so should never be trusted. An attacker can falsify the header to gain access to the page.
This fixed code only trusts the 'REMOTE_ADDR' header and so avoids the issue:
(good code)
Example Language: PHP
$requestingIP = '0.0.0.0'; if (array_key_exists('HTTP_X_FORWARDED_FOR', $_SERVER)) {
echo "This application cannot be accessed through a proxy."; return;
else{
$requestingIP = $_SERVER['REMOTE_ADDR'];
} ...
Be aware that 'REMOTE_ADDR' can still be spoofed. This may seem useless because the server will send the response to the fake address and not the attacker, but this may still be enough to conduct an attack. For example, if the generatePage() function in this code is resource intensive, an attacker could flood the server with fake requests using an authorized IP and consume significant resources. This could be a serious DoS attack even though the attacker would never see the page's sensitive content.
Web product uses the IP address in the X-Forwarded-For HTTP header instead of a server variable that uses the connecting IP address, allowing filter bypass.
PHP application uses IP address from X-Forwarded-For HTTP header, instead of REMOTE_ADDR.
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).
Description
