Adversaries may buy, steal, or download 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 developing their own exploits, an adversary may find/modify exploits from online or purchase them from exploit vendors.(Citation: Exploit Database)(Citation: TempertonDarkHotel)(Citation: NationsBuying)

In addition to downloading free exploits from the internet, adversaries may purchase exploits from third-party entities. Third-party entities can include technology companies that specialize in exploit development, criminal marketplaces (including exploit kits), or from individuals.(Citation: PegasusCitizenLab)(Citation: Wired SandCat Oct 2019) In addition to purchasing exploits, adversaries may steal and repurpose exploits from third-party entities (including other adversaries).(Citation: TempertonDarkHotel)

An adversary may monitor exploit provider forums to understand the state of existing, as well as newly discovered, exploits. There is usually a delay between when an exploit is discovered and when it is made public. An adversary may target the systems of those known to conduct exploit research and development in order to gain that knowledge for use during a subsequent operation.

Adversaries may use exploits during various phases of the adversary lifecycle (i.e. [Exploit Public-Facing Application](https://attack.mitre.org/techniques/T1190), [Exploitation for Client Execution](https://attack.mitre.org/techniques/T1203), [Exploitation for Privilege Escalation](https://attack.mitre.org/techniques/T1068), [Exploitation for Defense Evasion](https://attack.mitre.org/techniques/T1211), [Exploitation for Credential Access](https://attack.mitre.org/techniques/T1212), [Exploitation of Remote Services](https://attack.mitre.org/techniques/T1210), and [Application or System Exploitation](https://attack.mitre.org/techniques/T1499/004)).
Exploits
source_name: mitre-attack  url: https://attack.mitre.org/techniques/T1588/005  external_id: T1588.005     source_name: Exploit Database  description: Offensive Security. (n.d.). Exploit Database. Retrieved October 15, 2020.  url: https://www.exploit-db.com/     source_name: TempertonDarkHotel  description: Temperton, J. (2015, August 10). Hacking Team zero-day used in new Darkhotel attacks. Retrieved March 9, 2017.  url: https://www.wired.co.uk/article/darkhotel-hacking-team-cyber-espionage     source_name: NationsBuying  description: Nicole Perlroth and David E. Sanger. (2013, July 12). Nations Buying as Hackers Sell Flaws in Computer Code. Retrieved March 9, 2017.  url: https://www.nytimes.com/2013/07/14/world/europe/nations-buying-as-hackers-sell-computer-flaws.html     source_name: PegasusCitizenLab  description: Bill Marczak and John Scott-Railton. (2016, August 24). The Million Dollar Dissident: NSO Group’s iPhone Zero-Days used against a UAE Human Rights Defender. Retrieved December 12, 2016.  url: https://citizenlab.ca/2016/08/million-dollar-dissident-iphone-zero-day-nso-group-uae/     source_name: Wired SandCat Oct 2019  description: Zetter, K. (2019, October 3). Researchers Say They Uncovered Uzbekistan Hacking Operations Due to Spectacularly Bad OPSEC. Retrieved October 15, 2020.  url: https://www.vice.com/en/article/3kx5y3/uzbekistan-hacking-operations-uncovered-due-to-spectacularly-bad-opsec     