It was discovered that libytnef incorrectly handled malformed TNEF streams.
If a user were tricked into opening a specially crafted TNEF attachment, an
attacker could cause a denial of service or possibly execute arbitrary
code.
ubuntu.com/security/CVE-2017-6298
ubuntu.com/security/CVE-2017-6299
ubuntu.com/security/CVE-2017-6300
ubuntu.com/security/CVE-2017-6301
ubuntu.com/security/CVE-2017-6302
ubuntu.com/security/CVE-2017-6303
ubuntu.com/security/CVE-2017-6304
ubuntu.com/security/CVE-2017-6305
ubuntu.com/security/CVE-2017-6306
ubuntu.com/security/CVE-2017-6800
ubuntu.com/security/CVE-2017-6801
ubuntu.com/security/CVE-2017-6802