ssh version causing PCI scan failures
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@nogbadthebad I have no SSH allow rules except on the main LAN. I have no rules allowing SSH through on the WAN side and didn't think I needed a rule specifically blocking it since pfSense blocks by default on the WAN interface. I'll add a block rule just to see if that will satisfy the scanner.
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There is not rule needed if you have nothing on the wan - because yes the default is deny..
You sure this scan is seeing pfsense ssh? And not something in front of it, or where your forwarding too..
Did you put in a rule maybe on the floating tab?
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@johnpoz I agree they're likely doing the scan wrong, but trying to convince them of that is nearly impossible as communication is limited to a dispute process through their PCI scanning portal. I have only allowed their scanning IPs and IP blocks through the WAN to "this firewall" and not to the LAN. I have no public facing SSH allow rules and only allow SSH on the main LAN to the firewall. No other VLANs have SSH access to the firewall.
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This it would not be possible for them to see the ssh then.
So something missing from the puzzle..
If the device they are scanning from internally or externally does not have access to ssh on pfsense - how would they be seeing it? So either you have rules wrong, or they are scanning from somewhere they shouldn't be - ie like your lan..
Or they are seeing ssh that is not actually pfsense - say a device in front of pfsense? Or between pfsense and where they are scanning from.
The scanning of all IPs in the path is valid and part of pci, and yes meant to catch something like services open in the path or from the devices that should not be. While one way to correct is make sure the service(s) that are seen are up to whatever spec and security that is called for, the correct solution is also just make sure that service is not available from where being scanned from be it internal or external. This also meets criteria.. Its not that services can not be run on devices in the path.. Its just that these services can not be available from anything in the path, etc.
Example - while you might have a webgui say to admin a switch, that does not even support ssl.. This would clearly violate pci, but just need to make sure that anything in the path and used for pci can not access that service - and that service is only available from a device that is outside the scope of the pci validation - ie a managment vlan/pc only, etc.
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@jvcomputers said in ssh version causing PCI scan failures:
I have only allowed their scanning IPs and IP blocks through the WAN to "this firewall" and not to the LAN.
so basically you created an allow-all on WAN for their scanners? yea then they'll be able to get to ssh
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@johnpoz I'll have to review the rules again. The only thing in front of the pfSense is a bridged cable modem. I've added a specific block port 22 rule from WAN just in case that helps, but I'll also try locking down 22 to a specific IP on the LAN. The weird thing is, I forced a scan when I first put in the pfSense and it passed. Then, when they did their regularly scheduled scan three days later, it failed because of the CVEs I posted above. I put in the pfSense so we'd have better control over what is going on because their descriptions of failures were so random and vague. It's like they're trying anything they can to get their failure fees.
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@heper That is what they require, or at least what they describe. Is there another way? I tried locking it down further before but we failed the scan because they couldn't see anything at all and that wasn't good enough for them.
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@jvcomputers said in ssh version causing PCI scan failures:
but we failed the scan because they couldn't see anything at all
"We found nothing to exploit because you're blocking our scans so you fail!"
This makes my head hurt.
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Well you can not block them from everything - yeah that is failure... They should be able to see the services that are open to the public - ie the stuff available for pci, etc.
Unless those are locked to only the IPs that are used in the pci - for example your stores..
But yeah a specific block from their IPs to block everything would lead to a failure..
so basically you created an allow-all on WAN for their scanners?
Yeah that is also a freaking FAIL!! The point of scan is to validate you are setup securely.. So they should be scanning your normal firewall rules.. If you create a rule that allows them unfettered access to your firewall wan IP.. That would be fail right there for doing such a thing..
If you have your rules setup that only allow pci IP to access stuff, then proper setup would be to add their scanning IP(s) to these existing rules. And let them know that you needed to do this - because your normal rules lock to only specific IPs used in the pci process.
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@johnpoz I just tried only allowing the PCI scanners through to the two IPs on the LAN that process credit cards and it failed because it said the scanners weren't allowed, so it seems it must be allowed to scan "This Firewall (self)" or the scan will fail. It would help if the PCI rules were a bit more explicit about what they want to scan, but the entire world of PCI is almost as bad as HIPAA with its vagaries and contradictions.
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The only thing that should be open on your firewall is the stuff that is needed for pci to function.. The point of the scan is to find stuff that shouldn't be open.. Or if what your using for PCI is not up to specs for security - say for example you had a website on 80/443 used for pci - and the you were using say sslv3, or the httpd was not current, or was not patched for a specific vulnerability.
Modification of the rules to allow scan everything that "could" be open on the firewall invalidates the freaking test in the first place.
Nobody in their right mind would for example allow pfsense web gui access to the public internet.. If you open it up for them to scan - you should fail for even doing such a thing..
Where they would be justified in saying hey your ssh is not up to specs for security, is if you had that open to the public internet..
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@johnpoz Okay, but I don't have SSH open to the public internet. That's what I don't understand. The only things I have allowed through the firewall are the credit card company's processing IPs which are only allowed to the LAN IPs that process cards.
If I allow their scanners to only the same LAN IPs, they fail me because they have no access to scan the firewall. If I allow their scanners to access the firewall, they fail me because of the two SSH CVEs mentioned in my original post even though I don't have port 22 open to the public. Clearly, I don't understand some portion of this equation, but I don't know which.
If anyone has an example of how a successful setup for PCI scanning has been implemented, it would helpful. I'm sure there are thousands of CardPointe/CardConnect customers out there and someone must be successfully using pfSense other than this client. -
@jvcomputers said in ssh version causing PCI scan failures:
The only things I have allowed through the firewall are the credit card company's processing IPs which are only allowed to the LAN IPs that process cards.
You need to allow the company that is doing the scanning - which would be a "Approved Scanning Vendor (ASV)" access to the same stuff you are forwarding for your pci stuff..
Ie these rules
the credit card company's processing IPs which are only allowed to the LAN IPs that process cards.
Need to allow the IPs the scanning company will be coming from, or you need to temp open them up to all.. If the scanning company will not provide you the IPs.. So they can scan - they will need to see the stuff your doing with pci. If they can not see anything then clearly they will fail you.
But you don't need to allow them to scan EVERYTHING on the firewall that could be open.. I thought I clearly went over that already ;)
Post your wan rules and your port forwards - I take it your using an alias to allow the CC companies to access, in that alias add the ASV companies IPs
example: Qualys is an ASV.. These are the IPs they would be scanning from
"The scanner IP addresses are 64.39.96.0/20 (64.39.96.1-64.39.111.254). Depending on your network, it may be necessary to add the scanner IPs to your list of trusted IPs, so the service can send probes to the IP addresses in your account during scan processing. " -
@johnpoz I will post the rules shortly, but as I mentioned, I already tried allowing the ASV IPs access to the specific LAN IPs for CC processing and they didn't like that because they couldn't see the firewall. It seems the only time they don't fail me for not being able to scan is when they have their ASV IPs getting full access to "This firewall (Self)" and then they find the non-existent port 22 vulnerability.
Thanks for sticking with me on this. I'm sure it's just as monotonous for you as it is me.
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See my edit above.. I have no idea who your using for your ASV.. But they sure and F do not need to see every service that is possible on your firewall.. They only need access to the stuff used for PCI.. Or that is generally open on your firewall on your external IPs..
See the FAQ I just linked to as an example.
Show them your rules where their IPs have been allowed.. If they have problems with what they are seeing..
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@johnpoz CardPointe owns CardConnect (the credit card processing company) and CardPointe does their own PCI scanning - we have no choice in that.
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Ok - that is fine.. But there is NOTHING in the pci docs that say you have to lower your security stance to allow for such a scan.. Opening up ssh, when it is NOT open is not part of pci compliance..
Be like saying hey here eat this shrimp we are testing if you are allergic - but I don't eat shrimp! When I ate it I got sick.. So yeah if I eat it again I will get sick, so I don't eat it!! So why should I open up ssh to the internet for you to scan.. When I do not allow ssh -- scan me!! Do you see ssh open.. NO!! ;)
Your rules only allow specific IPs to use your port forwards.. Then add their IPs to those rules - that is all that is required to do..
Where you could get in trouble.. Is if you had ssh open, but you specifically blocked their IPs.. Show them your rules that only allow the trusted IPs, and that their scanning IPs have been added to the rules. And there are no other rules allowing stuff from other trusted IPs or that they have been blocked from, etc.
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@johnpoz They never specified specific ports to forward, so I just have rules set up to allow their processing IPs full access to the LAN IP that does the card processing - not port forwards, just an allow rule. It sounds like that is the problem?
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@jvcomputers said in ssh version causing PCI scan failures:
so I just have rules set up to allow their processing IPs full access to the LAN IP
Well then yeah they could hit you on some service that is not part of pci when they scan those IPs.. Ie if you have ssh open on one of these IPs they are scanning.. But again this would not be pfsense ssh service. But if you a rule open to IP X, that allows everything then sure anything on X is fair game to have to be secure.
Your rules should be set to only allow the ports required to do whatever it is your doing.. This is security 101.. If I am running a FTP server on IP 1.2.3.4, I sure do not also allow ssh, and httpd and snmp, and telnet and whatever else.. But if that is what you have is an any any rule to 1.2.3.4 then sure anything open on 1.2.3.4 is open to scrutiny.
If you have a rule that allows access to IP 1.2.3.4 and ssh is on 1.2.3.4, then yes ssh needs to meet their security requirements.. But that would not be pfsense ssh.
pci requires that they scan all your public facing IPs.. So yeah if you had ssh open on 1.2.3.5 while your pci stuff using 1.2.3.4 that would be a problem. But if you don't have anything open on 1.2.3.5 then its not a problem - they scanned it and no services are open..
This very common setup.. Where company owns public space, and .X is used for outbound traffic only, and .Y is used for inbound.. While they will scan both .x and .y - its fine if nothing shows as open on .x..
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@johnpoz They're just Windows 10 boxes, they don't have 22 open. I don't think Windows even has SSH server installed unless it's done so intentionally and it's not on either of these machines. Here's a shot of the rules I have in place.
The "CardPointe_DataCenter" alias is the one used for regular processing and consists of two domains: fts.cardconnect.com, cardpointe.com
CardPoint_Trustwave_24 is their block of IPs used for some of the scanning (64.37.231.0/24)
And the CardPoint_Trustwave_Others is a bunch of other IPs they use for scanning
