Buffer overflow in DNS resolver functions that perform lookup of network names and addresses, as used in BIND 4.9.8 and ported to glibc 2.2.5 and earlier, allows remote malicious DNS servers to execute arbitrary code through a subroutine used by functions such as getnetbyname and getnetbyaddr.
glibc2 does not properly clear the LD_DEBUG_OUTPUT and LD_DEBUG environmental variables when a program is spawned from a setuid program, which could allow local users to overwrite files via a symlink attack.