mktexlsr revision 36855, and before revision 36626 as packaged in texlive allows local users to write to arbitrary files via a symlink attack. NOTE: this vulnerability exists due to the reversion of a fix of CVE-2015-5700.
https://www.tug.org/svn/texlive/trunk/Build/source/texk/kpathsea/mktexlsr?view=log
https://www.tug.org/svn/texlive/trunk/Build/source/texk/kpathsea/mktexlsr?r1=19613&r2=22885
https://bugzilla.redhat.com/show_bug.cgi?id=1181167