sysdeps/posix/readdir_r.c in the GNU C Library (aka glibc or libc6) 2.18 and earlier allows context-dependent attackers to cause a denial of service (out-of-bounds write and crash) or possibly execute arbitrary code via a crafted (1) NTFS or (2) CIFS image.
https://bugzilla.redhat.com/show_bug.cgi?id=995839
http://secunia.com/advisories/55113
https://security.gentoo.org/glsa/201503-04
https://sourceware.org/bugzilla/show_bug.cgi?id=14699
http://www.mandriva.com/security/advisories?name=MDVSA-2013:283