I just heard from support about this issue, and its a known bug (internal bug SPL-160983) that they have decided to not fix. There is no impact to the system and there isn't a way to stop the error from triggering. Support said to ignore these errors going forward.
We have the same thing here. The regex itself seems working fine. It seems just another annoying error which could be safely ignore.
I think the resolution is to write a less greedy regex.
When / Where are you getting that error? If you're not actually doing a regex yourself, this is either a bug in splunk, or in some field extraction config or so in an add-on you have installed (although I'm not sure if that would result in errors presented in the GUI)?
Are you using this regex on the search bar with the rex command? If so, you have to use max_match.
The default for max_match is 1. Your regex is matching more than one value in an event.
Set max_match=0 for unlimited matches.
max_match is not really related to that error and will not solve it. If you get such an error when running regexes, it means your regex is poorly written and has too many matches (usually because of using stuff like
.*?, which cause the regex to match the string in many ways and require a lot of backtracking in the regex engine.
The solution is to write a better regex.