An adversary exploits a weakness in the way an application searches for external libraries to manipulate the execution flow to point to an adversary supplied library or code base. This pattern of attack allows the adversary to compromise the application or server via the execution of unauthorized code. An application typically makes calls to functions that are a part of libraries external to the application. These libraries may be part of the operating system or they may be third party libraries. If an adversary can redirect an application's attempts to access these libraries to other libraries that the adversary supplies, the adversary will be able to force the targeted application to execute arbitrary code. This is especially dangerous if the targeted application has enhanced privileges. Access can be redirected through a number of techniques, including the use of symbolic links, search path modification, and relative path manipulation.
Likelihood Of Attack
High
Typical Severity
Very High
Relationships
This table shows the other attack patterns and high level categories that are related to this attack pattern. These relationships are defined as ChildOf and ParentOf, and give insight to similar items that may exist at higher and lower levels of abstraction. In addition, relationships such as CanFollow, PeerOf, and CanAlsoBe are defined to show similar attack patterns that the user may want to explore.
Nature
Type
ID
Name
ChildOf
Meta Attack Pattern - A meta level attack pattern in CAPEC is a decidedly abstract characterization of a specific methodology or technique used in an attack. A meta attack pattern is often void of a specific technology or implementation and is meant to provide an understanding of a high level approach. A meta level attack pattern is a generalization of related group of standard level attack patterns. Meta level attack patterns are particularly useful for architecture and design level threat modeling exercises.
Detailed Attack Pattern - A detailed level attack pattern in CAPEC provides a low level of detail, typically leveraging a specific technique and targeting a specific technology, and expresses a complete execution flow. Detailed attack patterns are more specific than meta attack patterns and standard attack patterns and often require a specific protection mechanism to mitigate actual attacks. A detailed level attack pattern often will leverage a number of different standard level attack patterns chained together to accomplish a goal.
Detailed Attack Pattern - A detailed level attack pattern in CAPEC provides a low level of detail, typically leveraging a specific technique and targeting a specific technology, and expresses a complete execution flow. Detailed attack patterns are more specific than meta attack patterns and standard attack patterns and often require a specific protection mechanism to mitigate actual attacks. A detailed level attack pattern often will leverage a number of different standard level attack patterns chained together to accomplish a goal.
Detailed Attack Pattern - A detailed level attack pattern in CAPEC provides a low level of detail, typically leveraging a specific technique and targeting a specific technology, and expresses a complete execution flow. Detailed attack patterns are more specific than meta attack patterns and standard attack patterns and often require a specific protection mechanism to mitigate actual attacks. A detailed level attack pattern often will leverage a number of different standard level attack patterns chained together to accomplish a goal.
Detailed Attack Pattern - A detailed level attack pattern in CAPEC provides a low level of detail, typically leveraging a specific technique and targeting a specific technology, and expresses a complete execution flow. Detailed attack patterns are more specific than meta attack patterns and standard attack patterns and often require a specific protection mechanism to mitigate actual attacks. A detailed level attack pattern often will leverage a number of different standard level attack patterns chained together to accomplish a goal.
Standard Attack Pattern - A standard level attack pattern in CAPEC is focused on a specific methodology or technique used in an attack. It is often seen as a singular piece of a fully executed attack. A standard attack pattern is meant to provide sufficient details to understand the specific technique and how it attempts to accomplish a desired goal. A standard level attack pattern is a specific type of a more abstract meta level attack pattern.
Identify Target: The adversary identifies the target application and determines what libraries are being used.
Techniques
Find public source code and identify library dependencies.
Gain access to the system hosting the application and look for libraries in common locations.
Experiment
Deploy Malicious Libraries: The adversary crafts malicious libraries and deploys them on the system where the application is running, or in a remote location that can be loaded by the application.
Exploit
Redirect Library Calls to Malicious Library: Once the malicious library crafted by the adversary is deployed, the adversary will manipulate the flow of the application such that it calls the malicious library. This can be done in a variety of ways based on how the application is loading and calling libraries.
Techniques
Poison the DNS cache of the system so that it loads a malicious library from a remote location hosted by the adversary instead of the legitimate location
Create a symlink that tricks the application into thinking that a malicious library is the legitimate library.
Use DLL side-loading to place a malicious verison of a DLL in the windows directory.
Prerequisites
The target must utilize external libraries and must fail to verify the integrity of these libraries before using them.
Skills Required
[Level: Low]
To modify the entries in the configuration file pointing to malicious libraries
[Level: Medium]
To force symlink and timing issues for redirecting access to libraries
[Level: High]
To reverse engineering the libraries and inject malicious code into the libraries
Consequences
This table specifies different individual consequences associated with the attack pattern. The Scope identifies the security property that is violated, while the Impact describes the negative technical impact that arises if an adversary succeeds in their attack. 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 pattern will be used to achieve a certain impact, but a low likelihood that it will be exploited to achieve a different impact.
Scope
Impact
Likelihood
Authorization
Execute Unauthorized Commands
Access Control
Authorization
Bypass Protection Mechanism
Mitigations
Implementation: Restrict the permission to modify the entries in the configuration file.
Implementation: Check the integrity of the dynamically linked libraries before use them.
Implementation: Use obfuscation and other techniques to prevent reverse engineering the libraries.
Example Instances
In this example, the attacker using ELF infection that redirects the Procedure Linkage Table (PLT) of an executable allowing redirection to be resident outside of the infected executable. The algorithm at the entry point code is as follows... • mark the text segment writeable • save the PLT(GOT) entry • replace the PLT(GOT) entry with the address of the new lib call The algorithm in the new library call is as follows... • do the payload of the new lib call • restore the original PLT(GOT) entry • call the lib call • save the PLT(GOT) entry again (if its changed) • replace the PLT(GOT) entry with the address of the new lib call
Related Weaknesses
A Related Weakness relationship associates a weakness with this attack pattern. Each association implies a weakness that must exist for a given attack to be successful. If multiple weaknesses are associated with the attack pattern, then any of the weaknesses (but not necessarily all) may be present for the attack to be successful. Each related weakness is identified by a CWE identifier.
CAPEC mappings to ATT&CK techniques leverage an inheritance model to streamline and minimize direct CAPEC/ATT&CK mappings. Inheritance of a mapping is indicated by text stating that the parent CAPEC has relevant ATT&CK mappings. Note that the ATT&CK Enterprise Framework does not use an inheritance model as part of the mapping to CAPEC.