Several security issues were fixed in GnuTLS.
Hubert Kario discovered that GnuTLS incorrectly handled decoding a status response TLS extension. A remote attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service. This issue only applied to Ubuntu 16.04 LTS, Ubuntu 16.10 and Ubuntu 17.04. (CVE-2017-7507)
13 June 2017
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in GnuTLS.
Hubert Kario discovered that GnuTLS incorrectly handled decoding a status response TLS extension. A remote attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service. This issue only applied to Ubuntu 16.04 LTS, Ubuntu 16.10 and Ubuntu 17.04. (CVE-2017-7507)
It was discovered that GnuTLS incorrectly handled decoding certain OpenPGP certificates. A remote attacker could use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2017-7869)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.