A machine-actionable memory comprises one or more machine-actionable records arranged according to a data structure. Such a data structure may include links that respectively map between a remediation, at least one action, and at least two vulnerabilities. A method of selecting a remediation, that is appropriate to a vulnerability which is present on a machine to be remediated, may include: providing a machine-actionable memory as mentioned above; and indexing into the memory using: a given vulnerability identifier to determine (A) at least one of a remediation mapped thereto and (B) at least one action mapped to the given vulnerability identifier; and/or a given remediation to determine at least two vulnerabilities mapped thereto.