A libreswan bugfix update has been released for CentOS 7.

CentOS-announce: CEBA-2020:3354 CentOS 7 libreswan BugFix Update

CentOS Errata and Bugfix Advisory 2020:3354

Upstream details at :   https://access.redhat.com/errata/RHBA-2020:3354

The following updated files have been uploaded and are currently
syncing to the mirrors: ( sha256sum Filename )

x86_64:
c205e6c8f267b531e6cb7cdabe53c2b3cda12f1afd4735ece2a55f5c116d0159 libreswan-3.25-9.1.el7_8.x86_64.rpm

Source:
9fa72dc64fb2cbf7abd5961455b8d7de3e7bf228fb8380dc66ff74d573de1492 libreswan-3.25-9.1.el7_8.src.rpm