USN-5079-1 fixed vulnerabilities in curl. One of the fixes introduced a regression on Ubuntu 18.04 LTS. This update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
It was discovered that curl incorrect handled memory when sending data to an MQTT server. A remote attacker could use this issue to cause curl to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-22945)
Patrick Monnerat discovered that curl incorrectly handled upgrades to TLS. When receiving certain responses from servers, curl would continue without TLS even when the option to require a successful upgrade to TLS was specified. (CVE-2021-22946)
Patrick Monnerat discovered that curl incorrectly handled responses received before STARTTLS. A remote attacker could possibly use this issue to inject responses and intercept communications. (CVE-2021-22947)
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    "availability": "No subscription required",
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