USN-197-1: Shorewall vulnerability

10 October 2005

Shorewall vulnerability

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Releases

Details

A firewall bypass vulnerability has been found in shorewall. If
MACLIST_TTL was set to a value greater than 0 or MACLIST_DISPOSITION
was set to "ACCEPT" in /etc/shorewall/shorewall.conf, and a client was
positively identified through its MAC address, that client bypassed
all other policies/rules in place. This could allow external computers
to get access to ports that are intended to be restricted by the
firewall policy.

Please note that this does not affect the default configuration, which
does not enable MAC based client identification.

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Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 5.04
  • shorewall -
Ubuntu 4.10
  • shorewall -

In general, a standard system update will make all the necessary changes.

References

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Further reading