@taduemp63
Let me explain: The kernel module algif_aead had a major security vulnerability (dubbed copy.fail). There was no patch available when the vulnerability was made public, which is why people needed to put a "wrench" in the way to prevent this module from loading. On some distributions the module was loaded dynamically, but on Red Hat the module was built into the kernel and therefore the only way to prevent it from loading was to blacklist the module during boot (by configuring grub). This workaround was typically done by using the grubby tool. And the command that
@jwildeboer posted removes the the module from the blacklist again, because the prevention is no longer needed on a patched kernel.