Talon Mercenaries will only ambush you if your karma is High. Regulators will only attack if your karma is low. Remaining neutral will result in peaceful travel but you miss out on few advantages. ( Getting into Paradise Falls for free, people giving you items etc.) But Talon company will still be hostile. I don't know if they can BOTH attack you. It could be a glitch.
That would probably be a glitch unless your karma just changed from good to bad (or vice versa) recently.