nscd in the GNU C Library (aka glibc or libc6) before version 2.20 does not correctly compute the size of an internal buffer when processing netgroup requests, possibly leading to an nscd daemon crash or code execution as the user running nscd.
https://sourceware.org/bugzilla/show_bug.cgi?id=16695
https://seclists.org/bugtraq/2019/Sep/7
https://seclists.org/bugtraq/2019/Jun/14
http://www.securityfocus.com/bid/99071
http://seclists.org/fulldisclosure/2019/Sep/7