FreeBSD: VID-791841a3-d484-4878-8909-92ef9ce424f4 (CVE-2018-6952): patch -- multiple vulnerabilities

NVD reports: An issue was discovered in GNU patch through 2.7.6. There is a segmentation fault, associated with a NULL pointer dereference, leading to a denial of service in the intuit_diff_type function in pch.c, aka a "mangled rename" issue. A double free exists in the another_hunk function in pch.c in GNU patch through 2.7.6. GNU Patch version 2.7.6 contains an input validation vulnerability when processing patch files, specifically the EDITOR_PROGRAM invocation (using ed) can result in code execution. This attack appear to be exploitable via a patch file processed via the patch utility. This is similar to FreeBSD's CVE-2015-1418 however although they share a common ancestry the code bases have diverged over time.