Errata patches for Perl have been released for OpenBSD 6.6 and 6.7. Several problems in Perl's regular expression compiler could lead to corruption of the intermediate language state of a compiled regular expression.
Binary updates for the amd64, i386, and arm64 platforms are available via the syspatch utility. Source code patches can be found on the respective errata page: https://www.openbsd.org/errata66.html https://www.openbsd.org/errata67.html