A double-free condition exists in contrib/shpsort.c of shapelib 1.5.0 and older releases. This issue may allow an attacker to cause a denial of service or have other unspecified impact via control over malloc.Referenceshttps://github.com/OSGeo/shapelib/issues/39https://github.com/OSGeo/shapelib/commit/c75b9281a5b9452d92e1682bdfe6019a13ed819f
