This pattern of attack sees an adversary load a malicious resource into a program's standard path so that when a known command is executed then the system instead executes the malicious component. The adversary can either modify the search path a program uses, like a PATH variable or classpath, or they can manipulate resources on the path to point to their malicious components. J2EE applications and other component based applications that are built from multiple binaries can have very long list of dependencies to execute. If one of these libraries and/or references is controllable by the attacker then application controls can be circumvented by the attacker.
Likelihood Of Attack
The table below 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.
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.
The attacker must be able to write to redirect search paths on the victim host.
To identify and execute against an over-privileged system interface
The table below 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.
Execute Unauthorized Commands
Design: Enforce principle of least privilege
Design: Ensure that the program's compound parts, including all system dependencies, classpath, path, and so on, are secured to the same or higher level assurance as the program
Implementation: Host integrity monitoring
Another method is to redirect commands by aliasing one legitimate command to another to create unexpected results. the Unix command "rm" could be aliased to "mv" and move all files the victim thinks they are deleting to a directory the attacker controls. In a Unix shell .profile setting
alias rm=mv /usr/home/attacker
In this case the attacker retains a copy of all the files the victim attempts to remove.
A standard UNIX path looks similar to this
If the attacker modifies the path variable to point to a locale that includes malicious resources then the user unwittingly can execute commands on the attackers' behalf:
This is a form of usurping control of the program and the attack can be done on the classpath, database resources, or any other resources built from compound parts. At runtime detection and blocking of this attack is nearly impossible, because the configuration allows execution.
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.