CVE-2018-20969

do_ed_script in pch.c in GNU patch through 2.7.6 does not block strings beginning with a ! character. NOTE: this is the same commit as for CVE-2019-13638, but the ! syntax is specific to ed, and is unrelated to a shell metacharacter.

CVE-2019-13636

In GNU patch through 2.7.6, the following of symlinks is mishandled in certain cases other than input files. This affects inp.c and util.c.

CVE-2015-1396

A Directory Traversal vulnerability exists in the GNU patch before 2.7.4. A remote attacker can write to arbitrary files via a symlink attack in a patch file. NOTE: this issue exists because of an incomplete fix for CVE-2015-1196.