Updated glibc package fixes security vulnerability:

The function wordexp() fails to properly handle the WRDE_NOCMD
flag when processing arithmetic inputs in the form of $((… “))
where … can be anything valid. The backticks in the arithmetic
epxression are evaluated by in a shell even if WRDE_NOCMD forbade
command substitution. This allows an attacker to attempt to pass
dangerous commands via constructs of the above form, and bypass the
WRDE_NOCMD flag. This update fixes the issue (CVE-2014-7817).