Security mechanism evaluation service

Methods and apparatus for a security mechanism evaluation service are disclosed. A storage medium stores program instructions that when executed on a processor define a programmatic interface enabling a client to submit an evaluation request for a security mechanism. On receiving an evaluation request from a client indicating a particular security mechanism using public-key encryption, the instructions when executed, identify resources of a provider network to be used to respond. The instructions, when executed, provide to the client, one or more of: (a) a trustworthiness indicator for a certificate authority that issued a public-key certificate in accordance with the particular security mechanism; (b) a result of a syntax analysis of the public-key certificate; or (c) a vulnerability indicator for a key pair.