Adversaries may exploit a system or application vulnerability to bypass security features. Exploitation of a vulnerability occurs when an adversary takes advantage of a programming error in a program, service, or within the operating system software or kernel itself to execute adversary-controlled code. Vulnerabilities may exist in defensive security software that can be used to disable or circumvent them.

Adversaries may have prior knowledge through reconnaissance that security software exists within an environment or they may perform checks during or shortly after the system is compromised for [Security Software Discovery](https://attack.mitre.org/techniques/T1518/001). The security software will likely be targeted directly for exploitation. There are examples of antivirus software being targeted by persistent threat groups to avoid detection.

There have also been examples of vulnerabilities in public cloud infrastructure of SaaS applications that may bypass defense boundaries (Citation: Salesforce zero-day in facebook phishing attack), evade security logs (Citation: Bypassing CloudTrail in AWS Service Catalog), or deploy hidden infrastructure.(Citation: GhostToken GCP flaw)
Exploitation for Defense Evasion
source_name: mitre-attack  url: https://attack.mitre.org/techniques/T1211  external_id: T1211     source_name: Salesforce zero-day in facebook phishing attack  description: Bill Toulas. (2023, August 2). Hackers exploited Salesforce zero-day in Facebook phishing attack. Retrieved September 18, 2023.  url: https://www.bleepingcomputer.com/news/security/hackers-exploited-salesforce-zero-day-in-facebook-phishing-attack/     source_name: Bypassing CloudTrail in AWS Service Catalog  description: Nick Frichette. (2023, March 20). Bypassing CloudTrail in AWS Service Catalog, and Other Logging Research. Retrieved September 18, 2023.  url: https://securitylabs.datadoghq.com/articles/bypass-cloudtrail-aws-service-catalog-and-other/     source_name: GhostToken GCP flaw  description: Sergiu Gatlan. (2023, April 21). GhostToken GCP flaw let attackers backdoor Google accounts. Retrieved September 18, 2023.  url: https://www.bleepingcomputer.com/news/security/ghosttoken-gcp-flaw-let-attackers-backdoor-google-accounts/     