Jenkins Credentials Plugin 1380.va435002fa924 and earlier, except 1371.1373.v4ebfab7161e9, does not redact encrypted values of credentials using the SecretBytes type (e.g., Certificate credentials, or Secret file credentials from Plain Credentials Plugin) when accessing item config.xml via REST API or CLI.

This allows attackers with Item/Extended Read permission to view encrypted SecretBytes values in credentials.

This issue is similar to SECURITY-266 in the 2016-05-11 security advisory, which applied to the Secret type used for inline secrets and some credentials types.

Credentials Plugin 1381.v2c3a12074dab redacts the encrypted values of credentials using the SecretBytes type in item config.xml files.

This fix is only effective on Jenkins 2.479 and newer, LTS 2.462.3 and newer. While Credentials Plugin 1381.v2c3a12074dab can be installed on Jenkins 2.463 through 2.478 (both inclusive), encrypted values of credentials using the SecretBytes type will not be redacted when accessing item config.xml via REST API or CLI.