2,184. Mamzerim by Rabbinic Enactment

Hilchos Issurei Biah 15:20

Even if there’s a rumor that a woman has committed adultery and everyone is gossiping about her, we are not concerned that her children might be mamzerim. Rather, the presumption is that her most frequent partner is her husband (and therefore likely the father). One may marry this woman’s daughter even at the outset. As far as the woman herself, we do suspect that she may be a zonah (a woman who has engaged in intimacy with prohibited relations). If she was exceedingly promiscuous, then we are also concerned about her children’s status.

Hilchos Issurei Biah 15:21

Under Biblical law, one suspected of being a mamzer may join the general Jewish marriage pool. Deuteronomy 23:3 only prohibits a mamzer from joining the marriage pool – a definite mamzer may not marry into the general Jewish population but a person whose status is in doubt may. It was the Sages who raised the bar vis-à-vis lineage and prohibited those of doubtful status from joining the general marriage pool. A man and a woman who are definitely mamzerim may marry one another; a doubtful mamzer, a shetuki and an asufi may not marry women who were born Jewish.