libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse, if one of them matches the setup. Due to errors in the logic, the config matching function did not take 'issuer cert' into account and it compared the involved paths *case insensitively*, which could lead to libcurl reusing wrong connections. File paths are, or can be, case sensitive on many systems but not all, and can even vary depending on used file systems. The comparison also didn't include the 'issuer cert' which a transfer can set to qualify how to verify the server certificate.
Created curl tracking bugs for this issue:
Affects: fedora-all [bug 1984327]
This issue has been addressed in the following products:
Red Hat Enterprise Linux 8
Via RHSA-2021:3582 https://access.redhat.com/errata/RHSA-2021:3582
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):