Central defender Taylor damaged a hamstring during Sunday's 2-0 Barclays Premier League defeat at Southampton, while France midfielder Cabaye is expected to undergo a second groin operation in the next 24 hours.
Asked if the news on Taylor was worse than first feared, the manager said: "It probably is.
"It's about six to eight weeks, we think, so it's another blow. We are in a run of bad luck for us.
"He's an important player and we hope for a speedy recovery.
"He's cursing his luck a little bit, but unfortunately for Steven, his record is that he does pick up injuries.
"Maybe the fact that we have had to call upon him more than perhaps we would like with the injuries and Colo's [Fabricio Coloccini's] suspension has probably compounded the issue."
On Cabaye, Pardew added: "He's had one side of his groin done and that caused a potential weakness in the other side, so that needs to be done.
"That will be done, I think, today or tomorrow and he will probably be out for eight weeks."