This was a bit surprising. Not cause of the vulnerability, but because it was making the news since it was actually really old information. The vulnerability in the JetDirect protocol (port 9100) used by HP Printers has been known for years. I first learned about it in 2012 from a team member on a Red Cell, no idea how long he had known about it. Here is an article explaining it in 2013. https://www.nowsecure.com/blog/2013/01/14/exploiting-printers-via-jetdirect-vulnerabilities/
Not ragging on the guy that reported it, but all of his headline making security news articles have been nothing more than searching Shodan results for already known issues.
The vulnerability is semi useful on internal networks for hosting malicious files (sometimes code coming from an internal IP is trusted or evades CIRT scrutiny). In theory this makes them the ideal place for miscreants to host malware since http(s) traffic is the best way to blend in with normal traffic and avoid firewall rules.
What this article failed to acknowledge is that 95 out of 100 times uploading a very small file to the HP through JetDirect will crash the service and the server from my testing. In my opinion the threat that these unsecured printers pose on the internet is minimal at best with regards to this. The miscreants that push malware can buy cheap server space using stolen credit cards or anonymous payment methods. Additionally, real web servers that can handle traffic can be infected via WordPress vulnerabilities and misconfigurations nearly as easily as these HP printers with the aid of Shodan.io for targeting. The last thing a criminal wants is for the spear phishing to be successful but the infections to fail due to crappy hosting for the malware.
A more accurate assessment of this threat would be to comb the Shodan results for “Port:9100” looking for malicious files hosted on these HP printers. I am guessing the number would be nearly non-existent and not cause the malware pushers don’t know about the opportunity. Cause it isn’t worth their time.
IMHO a more worthy use of multi function devices for malicious purposes would be trying to configure any digital sender functionality to go through your personal SMTP gateway so that you can take copies of internal documents. If they are using LDAP for authentication that also opens up the possibility of stealing credentials if you can pipe the queries through the attacker box.
Another printer bites the dust after uploading a file…