A DNS proxy is configured on an internet-facing zone
At a glance
Base severity
Area
Platform
Evidence level
Benchmark reference
Reads the export, not the device
ConfigProof reads a configuration export. This control is evaluated against the objects in that file, and it reports what the file says. It does not connect to the device and sees no traffic, so a finding here describes the configuration, not what the firewall is doing right now.
Why it matters
A DNS proxy configured on an internet facing interface is set to answer whoever reaches that interface: an open resolver that can be used to amplify attacks against others and that tells outsiders about internal names.
How to fix it
Web interface
The steps below are written for the web interface. A finding raised on your own export carries the same steps with your object names filled in.
- Remove the interface from the DNS proxy under Network, DNS Proxy, and keep the proxy on internal interfaces only.
Command line
PAN-OS CLI
delete network dns-proxy <object-name> interface <interface>An example. Values in angle brackets are yours to supply; a finding on your own export fills in the names it read. Nothing here commits. Review the candidate configuration, then commit it yourself.
Read it back
show network dns-proxy <object-name>Values to fill in2
- <object-name>
- The object's name, as it appears on your firewall
- <interface>
- The interface to change
How to confirm the fix
- Confirm a query sent to the interface from outside is not answered.
Limits
- The zone is judged internet facing from its name only.
- An interface that is a template variable is recorded rather than judged.
Compliance references
No benchmark recommendation is mapped to this control in this version.
See it on your own firewall
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