COMMAND
httpd
SYSTEMS AFFECTED
Systems running Apache v1.2b8
PROBLEM
Valgamon discovered a problem in the eighth beta of Apache v1.2.
When the proxy module is compiled into the server executable, and
the access configuration file is set up for host-based denial, an
attacker can still access the proxy and effectively appear to be
coming from your host while browsing the web. This problem seems
to be platform-independent.
He was testing Apache's viability as an alternative to the TIS
Firewall Toolkit's HTTP proxy. The access.conf file had been
correctly set to deny all hosts access to the proxy except for my
testing machine, as follows:
<Directory proxy:*>
<Limit GET>
order deny,allow
deny from all
allow from testing.machine.ip.address
</Limit>
</Directory>
Yet it still allows any host to retrieve any website as long as
you leave off the trailing forward slash from the GET request.
When telnetting to the proxy port from hosts that should be
denied access to the proxy, Valgamon issued two very similar GET
requests and got two different results.
GET http://www.yahoo.com <--- gives you the page!! It should not!
GET http://www.yahoo.com/ <--- denies you, like it's supposed to.
The only difference is that forward slash on the end of the 2nd
request.
SOLUTION
Chuck Murcko at apache.org confirmed that this is a new bug and
assured that will be fixed in 1.2b10. Temporary Fix: use a <File>
block instead of <Directory>.