The wordexp function in GNU C Library (aka glibc) 2.21 does not enforce the WRDE_NOCMD flag, which allows context-dependent attackers to execute arbitrary commands, as demonstrated by input containing “$((` `))”.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-7817
Reference (s):
- BID:71216
- URL: http://www.securityfocus.com/bid/71216
- http://linux.oracle.com/errata/ELSA-2015-0016.html
- http://linux.oracle.com/errata/ELSA-2015-0092.html
- http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html