[2/27/24, 11:00 AM EST] CSRC has been experiencing technical issues. If you are unable to access a CSRC page or resource, or get a 503 error, please try reloading the page several times--it may help to wait a few minutes before trying again. We apologize for the inconvenience, and hope to have a solution in place next week.
A security event, or a combination of multiple security events, that constitutes a security incident in which an intruder gains, or attempts to gain, access to a system or system resource without having authorization to do so.
CNSSI 4009-2015 from IETF RFC 4949 Ver 2
CNSSI 4009-2015 under penetration
any set of actions that attempts to compromise the integrity, confidentiality, or availability of a resource
NIST SP 800-35 under Intrusion