C5 Field Guideunofficial

CRY · Cryptography and Key Management

CRY-12 Cryptographic Key Transition Management

1 sub-criterion

Changed since C5:2020 · formerly CRY-04

Basic criterion

Dissolved the former key management criterion and moved key transition management into its own criterion with extended requirements.

Additional criterion

Dissolved the former key management criterion and moved key transition management into its own criterion, to which the former key management additional criterion does not apply.

Wording in C5:2020

Basic criterion

Procedures and technical safeguards for secure key management in the area of responsibility of the Cloud Service Provider include at least the following aspects:

  • Generation of keys for different cryptographic systems and applications;
  • Issuing and obtaining public-key certificates;
  • Provisioning and activation of the keys;
  • Secure storage of keys (separation of key management system from application and middleware level) including description of how authorised users get access;
  • Changing or updating cryptographic keys including policies defining under which conditions and in which manner the changes and/or updates are to be realised;
  • Handling of compromised keys;
  • Withdrawal and deletion of keys; and
  • If pre-shared keys are used, the specific provisions relating to the safe use of this procedure are specified separately.

Additional criterion

Keys should be withdrawn or deleted e.g. in the event of compromise or employee changes. The Cloud Service Provider protects the keys which are created and inserted into the cloud service by the cloud customers according to the same criteria as the keys created by the Cloud Service Provider.

All changes since C5:2020

Basic criterion

CRY-12.01B

The cloud service provider has documented and implemented procedures to oversee the transition of cryptographic keys, including their movement into and out of suspension. These procedures ensure that all key transitions are thoroughly monitored, reviewed, and approved to maintain security and comply with applicable laws and regulations.

Supplementary information

Suspension of a cryptographic key refers to a temporary state in which the key is disabled and cannot be used for cryptographic operations but may later be reactivated. Deactivation of a cryptographic key, in contrast, represents a permanent state in which the key is withdrawn from use and cannot be reactivated.

BSI text from C5:2026 and its changelog: © Federal Office for Information Security 2026, reproduced unchanged under CC BY-ND 4.0. Unofficial site, not affiliated with BSI. Licence and sources