The lack of details in the advisory is only a minor impediment for a malicious person who wants to figure out how to implement their own exploit for this vulnerability. Anyone can read the patch that fixes it and figure it out.

TLDR: if you run your own instance, update it ASAP. If an instance you rely on hasn’t updated yet, consider asking its admins to do so. And if they don’t update it soon, you might want to reconsider your choice of instance.