Updated postgresql packages fix security vulnerabilities:
Given a suitable SECURITY DEFINER function, an attacker can execute arbitrary SQL under the identity of the function owner. An attack requires EXECUTE permission on the function, which must itself contain a function call having inexact argument type match. For example, length('foo'::varchar) and length('foo') are inexact, while length('foo'::text) is exact (CVE-2019-10208).
In a database containing hypothetical, user-defined hash equality operators, an attacker could read arbitrary bytes of server memory. For an attack to become possible, a superuser would need to create unusual operators. It is possible for operators not purpose-crafted for attack to have the properties that enable an attack, but we are not aware of specific examples (CVE-2019-10209).
This update also fixes over 40 bugs that were reported in the last several months. See the upstream release notes for details.