What evidence do auditors commonly ask for on CRY-02 Encryption of data for transmission (transport encryption)?

Protocol and cipher suite configuration of public-facing service endpoints; External scan output confirming deprecated protocol versions are refused; Certificate inventory for the endpoints terminating customer traffic; Flow design identifying which transmissions leave the provider network over public paths.

What is the most common gap auditors find on CRY-02?

Legacy endpoints still negotiating outdated protocol versions for backward compatibility

BSI C5 (121-criteria catalogue) · C5: Cryptography and Key Management

`CRY-02` Encryption of data for transmission (transport encryption)

Implement procedures and technical measures applying strong encryption and authentication to cloud customer data whenever it is transmitted over public networks, so traffic in transit can be neither read nor spoofed.

Source: BSI C5 (121-criteria catalogue), CRY-02. The statement above is our statement of the clause, read from the published text and cited so you can check it against the official text, not the instrument verbatim. Open BSI C5 (121-criteria catalogue) in the compliance library.

The edition of the catalogue is not stamped here; check the edition your attestation is issued against.

artefacts

held by a system

at each review

easy

to go live

Key management / PKI

where the evidence lives

teal = a system already holds it · olive = produced at each review. To go live: easy when half or more of the artefacts are already held by a system, moderate from a quarter to a half, hard below a quarter.

These are the artefacts auditors commonly ask for on this requirement, our guidance rather than text from the standard. Your assessor decides what is sufficient in your context, and asks for samples across the period when a report covers one.

system holds itEvidence a system already holds

Protocol and cipher suite configuration of public-facing service endpoints · Key management / PKI
External scan output confirming deprecated protocol versions are refused · Vulnerability scanner / patch tooling
Certificate inventory for the endpoints terminating customer traffic · Key management / PKI

periodic reviewEvidence produced at each review

none for this control

governing documentDocuments that govern the control

Flow design identifying which transmissions leave the provider network over public paths · Policy repository / GRC workspace

First move

Automate the pull from your Key management / PKI. Key inventory, rotation dates and certificate expiry from the KMS or PKI.

Common gaps auditors find

Legacy endpoints still negotiating outdated protocol versions for backward compatibility
Encryption terminated at a load balancer and carried onward unprotected across a public link
Peer authentication not enforced, so the identity of the far end is never validated

Do this for your whole sheet

Paste the rows you run your controls from and get this mapping for every control at once, with the periodic-review ones flagged and a first move per row. No account for the first run.

Build my evidence sheet

CRY-01 Policy for the use of encryption procedures and key management · CRY-03 Encryption of sensitive data for storage