This update for squid3 fixes the following issues:
Fixed incorrect buffer handling that can result in cache poisoning, remote execution, and denial of service attacks when processing ESI responses (CVE-2019-12519, CVE-2019-12521, bsc#1169659)
Fixed handling of hostname in cachemgr.cgi (CVE-2019-18860, bsc#1167373)
Fixed a potential denial of service when processing TLS certificates during HTTPS connections (CVE-2020-14059, bsc#1173304)
Fixed a potential denial of service associated with incorrect buffer management of HTTP Basic Authentication credentials (bsc#1141329, CVE-2019-12529)
Fixed a security issue in extlmgroup_acl when processing NTLM Authentication credentials. (CVE-2020-8517, bsc#1162691)
Fixed Cross-Site Request Forgery in HTTP Request processing (CVE-2019-18677, bsc#1156328)
Disable urn parsing and parsing of unknown schemes (bsc#1156329, CVE-2019-12523, CVE-2019-18676)