OpenSLP as used in ESXi and the Horizon DaaS appliances has a heap overwrite issue. VMware has evaluated the severity of this issue to be in the Critical severity range with a maximum CVSSv3 base score of 9.8.
https://access.redhat.com/errata/RHSA-2019:4240
https://access.redhat.com/errata/RHSA-2020:0199
https://security.gentoo.org/glsa/202005-12
http://www.openwall.com/lists/oss-security/2019/12/10/2
http://www.openwall.com/lists/oss-security/2019/12/11/2
http://www.vmware.com/security/advisories/VMSA-2019-0022.html