Yes its two hanging pointers related to the upload progress handler that can be used for RCE after some heap grooming, disabling upload progress means that the function that contains the vulnerable code never runs.
Details about the exploits have already been leaked on twitter, don't want to put the details here but if its correct then it can be mitigated by setting session.upload_progress.enabled = Off
Looks like details about the exploits have already leaked on twitter, if the info is correct then it can be mitigated by setting session.upload_progress.enabled = Off until you get the opportunity to update