CVE-2021-22924: Use of Incorrectly-Resolved Name or Reference

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 does not take issuercert 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.