PostGIS < 3.7.0beta2 Out-of-Bounds Read via FlatGeobuf Buffer

PostGIS before 3.7.0beta2 contains an out-of-bounds read vulnerability that allows attackers to cause memory disclosure or a server crash by supplying a malformed FlatGeobuf buffer. The FlatGeobuf property metadata decoder verifies that a string length field is present but fails to verify that the subsequent string body is contained within the supplied buffer before materializing it into a SQL-visible value, enabling memory disclosure or denial of service.

PostGIS 2.x before 2.3.3, as used with PostgreSQL, allows remote attackers to cause a denial of service via crafted ST_AsX3D function input, as demonstrated by an abnormal server termination for "SELECT ST_AsX3D('LINESTRING EMPTY');" because empty geometries are mishandled.