The NAT code (1) ip_nat_proto_tcp.c and (2) ip_nat_proto_udp.c
in Linux kernel 2.6 before 2.6.13 and 2.4 before 2.4.32-rc1
incorrectly declares a variable to be static, which allows
remote attackers to cause a denial of service (memory
corruption) by causing two packets for the same protocol to be
NATed at the same time, which leads to memory corruption.
This issue was already fixed in EL4 in linux-2.6.12-network.patch but not in EL3
which looks vulnerable to this issue.
RHEL3 looks vulnerable to me, too.
Reassigning to Don at Linda's request.
A fix for this problem has just been committed to the RHEL3 U7
patch pool this evening (in kernel version 2.4.21-37.8.EL).
A fix for this problem has also been committed to the RHEL3 E7
patch pool this evening (in kernel version 2.4.21-37.0.1.EL).
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.