Since today RSA SecurID 4.2.1 has been failing on Big Sur and possibly on other versions.

The app shows a general error but a message in the console says:

SecurID "Trust evaluate failure: [ca1 BlackListedLeaf]"

Regarding to the docs BlackListedLeaf tells that a certificate was blacklisted.

RSA SecurID is a mechanism developed by RSA for performing two-factor authentication for a user to a network resource. RSA Security LLC provides their technologies to 1 billion of consumers.