A denial of service vulnerability was found in rsyslog in the imptcp module. An attacker could send a specially crafted message to the imptcp socket, which would cause rsyslog to crash. Versions before 8.27.0 are vulnerable.
https://access.redhat.com/errata/RHBA-2019:2501
https://access.redhat.com/errata/RHSA-2019:2110
https://access.redhat.com/errata/RHSA-2019:2437
https://access.redhat.com/errata/RHSA-2019:2439
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16881
https://lists.debian.org/debian-lts-announce/2022/05/msg00028.html