from referrer header fields. A remote attacker could possibly use this
issue to obtain sensitive information. (CVE-2021-22876)
Mingtao Yang discovered that curl incorrectly handled session tickets when
using an HTTPS proxy. A remote attacker in control of an HTTPS proxy could
use this issue to bypass certificate checks and intercept communications.
This issue only affected Ubuntu 20.04 LTS and Ubuntu 20.10.