Adversaries may develop exploits that can be used during targeting. An exploit takes advantage of a bug or vulnerability in order to cause unintended or unanticipated behavior to occur on computer hardware or software. Rather than finding/modifying exploits from online or purchasing them from exploit vendors, an adversary may develop their own exploits. Adversaries may use information acquired via Vulnerabilities to focus exploit development efforts. As part of the exploit development process, adversaries may uncover exploitable vulnerabilities through methods such as fuzzing and patch analysis.
As with legitimate development efforts, different skill sets may be required for developing exploits. The skills needed may be located in-house, or may need to be contracted out. Use of a contractor may be considered an extension of that adversary's exploit development capabilities, provided the adversary plays a role in shaping requirements and maintains an initial degree of exclusivity to the exploit.
Adversaries may use exploits during various phases of the adversary lifecycle (i.e. Exploit Public-Facing Application, Exploitation for Client Execution, Exploitation for Privilege Escalation, Exploitation for Defense Evasion, Exploitation for Credential Access, Exploitation of Remote Services, and Application or System Exploitation).
This technique cannot be easily mitigated with preventive controls since it is based on behaviors performed outside of the scope of enterprise defenses and controls.
Much of this activity will take place outside the visibility of the target organization, making detection of this behavior difficult. Detection efforts may be focused on behaviors relating to the use of exploits (i.e. Exploit Public-Facing Application, Exploitation for Client Execution, Exploitation for Privilege Escalation, Exploitation for Defense Evasion, Exploitation for Credential Access, Exploitation of Remote Services, and Application or System Exploitation).