COMMAND
bind()
SYSTEMS AFFECTED
All systems running BIND
PROBLEM
The following informations is based on Secure Networks Inc. and
CORE Seguridad de la Informacion advisory.
A failure to check whether hostname lengths exceed MAXHOSTNAMELEN
in size. This results in potential buffer overflows in programs
which expect the BIND resolver to only return a maximum hostname
length of MAXHOSTNAMELEN.
BIND allows passing of hostnames larger than MAXHOSTNAMELEN in
size to programs. As many programs utilize buffers of size
MAXHOSTNAMELEN and copy the results from a query into these
buffers, an overflow can occur. This can allow an attacker to
execute arbitrary commands on a remote server in a worst case
scenario.
SOLUTION
In original advisory there was patch, but weak one so it is not
placed here. Go to www.secnet.com and see it for yourself. You
should apply BIND 4.9.5-P2 or BIND 8.1-REL.