Brand new install, CPHulk links broken

Just installed CPanel/WHM on a brand new server, and have already encountered a problem: in CPHulk EMail notifications, the links to blacklist or whitelist IPs/ranges do not work. More specifically, the links work in that they take you to the in page, which a loads - but it's impossible to actually login via that page. So the links work, but not as they're supposed to. After entering the password & clicking the "Proceed..." button, I'm just getting an endless loop - it sends me back to the same page, with the same unhelpful error message: HTTP error 401 Invalid Security Token I've checked on another CPanel server that I manage - it appears to be broken in the same way (the same vague error message about an "Invalid Security Token,") but the login actually works on that server. This is a brand new server, running the current release version of CPanel/WHM (88.0.5) - and the only configuration that I've done with CPHulk so far was to enable it, and copy some settings from another server where the CPHulk links do work correctly. Which all indicates that is issue is due to some kind of glitch/error in CPanel. Please advise when it will be fixed, or at least the steps to work around it.