USN-5550-1: GnuTLS vulnerabilities

It was discovered that GnuTLS incorrectly handled certain memory
operations. A remote attacker could possibly use this issue to cause GnuTLS
to crash, resulting in a denial of service. This issue only affected Ubuntu
18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2021-4209)

It was discovered that GnuTLS incorrectly handled the verification of
certain pkcs7 signatures. A remote attacker could use this issue to cause
GnuTLS to crash, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2022-2509)

gnutls vulnerabilities