All 3 browsers bring up this error after clicking the forum sign in button:
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I was redirected to change my Adobe ID password because Adobe let pirates run amuck all through everyone's personal info, however even after updating my log on and signing in on the main adobe site, I still can't log on to forums.
BTW... I'm posting from my office account.
Please clear your browser cookies and try again. There's an ongoing problem within the forums CDN, it's unrelated to the recent security alert but it does mean that if you're unlucky and connect to the wrong server node, the login page fails. Clearing your cookies forces the server to redirect you.