OpenCRX before v5.2.2 was discovered to be vulnerable to password enumeration due to the difference in error messages received during a password reset which could enable an attacker to determine if a username, email or ID is valid.
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not.