popd controlled free:A denial of service flaw was found in the way bash handled popd commands. A poorly written shell script could cause bash to crash resulting in a local denial of service limited to a specific bash session.Arbitrary code execution via malicious hostname:An arbitrary command injection flaw was found in the way bash processed the hostname value. A malicious DHCP server could use this flaw to execute arbitrary commands on the DHCP client machines running bash under specific circumstances.Specially crafted SHELLOPTS+PS4 variables allows command substitution:An arbitrary command injection flaw was found in the way bash processed the SHELLOPTS and PS4 environment variables. A local, authenticated attacker could use this flaw to exploit poorly written setuid programs to elevate their privileges under certain circumstances