Perl before 5.30.3 has an integer overflow related to mishandling of a "PL_regkind[OP(n)] == NOTHING" situation. A crafted regular expression could lead to malformed bytecode with a possibility of instruction injection.
https://www.oracle.com/security-alerts/cpuoct2021.html
https://www.oracle.com/security-alerts/cpuoct2020.html
https://www.oracle.com/security-alerts/cpujan2022.html
https://www.oracle.com/security-alerts/cpujan2021.html
https://www.oracle.com/security-alerts/cpuapr2022.html
https://www.oracle.com/security-alerts/cpuApr2021.html
https://www.oracle.com//security-alerts/cpujul2021.html
https://security.netapp.com/advisory/ntap-20200611-0001/
https://security.gentoo.org/glsa/202006-03
https://github.com/perl/perl5/commit/3295b48defa0f8570114877b063fe546dd348b3c
https://github.com/perl/perl5/commit/0a320d753fe7fca03df259a4dfd8e641e51edaa8
https://github.com/Perl/perl5/compare/v5.30.2...v5.30.3
https://github.com/Perl/perl5/blob/blead/pod/perl5303delta.pod
http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00044.html