An issue was discovered in Squid before 4.10. It allows a crafted FTP server to trigger disclosure of sensitive information from heap memory, such as information associated with other users' sessions or non-Squid processes.
http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00012.html
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00010.html
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00018.html
https://lists.debian.org/debian-lts-announce/2020/07/msg00009.html
https://security.gentoo.org/glsa/202003-34
https://usn.ubuntu.com/4289-1/