The Candlepin component of Red Hat Satellite was affected by an improper authentication flaw. Few factors could allow an attacker to use the SCA (simple content access) certificate for authentication with Candlepin.
https://github.com/candlepin/candlepin/pull/3199
https://github.com/candlepin/candlepin/pull/3198
https://github.com/candlepin/candlepin/pull/3197