Printers sit quietly in corners—trusted, ignored, and rarely patched. Yet they run full operating systems, store documents, and connect directly to your internal network. Vulnerability scanning for printers isn’t just IT hygiene—it’s emergency defense. Most breaches start with the device nobody thinks is a threat.
Why Traditional Scanners Miss Printer Vulnerabilities
Generic vulnerability scanners treat printers like dumb peripherals. They ping ports, check HTTP headers, maybe sniff SNMP. That’s not enough. Modern printers run Linux kernels, embedded web servers, and even Java-based management consoles—all potential exploit surfaces.
And many enterprise-grade scanners skip port 9100 (JetDirect) or ignore PostScript interpreters entirely. Result? False negatives. Clean reports. And compromised print queues serving as pivot points into your financial or HR systems.
Vulnerability scanning for printers: A Practical Step-by-Step Guide
Map Every Networked Printer First
Start with discovery—not assumptions. Use Nmap with aggressive service detection: nmap -sV -p 515,631,9100,9101,9200 [subnet]. Don’t forget wireless and MFPs—they’re often on separate VLANs but still routable.
Prioritize by Function and Data Flow
A reception-area printer handling visitor badges poses less risk than a finance department MFP archiving invoices to internal storage. Tag each device by data sensitivity, not just IP address.
Run Targeted, Protocol-Aware Scans
Forget blanket scans. Use tools that speak printer-native protocols:
| Tool | Printer Protocols Covered | Cost | Best For |
|---|---|---|---|
| Nessus Professional | IPP, LPD, JetDirect, SNMPv3 | $2,995/year | Large enterprises with mixed fleets |
| OpenVAS (Greenbone) | Basic JetDirect, HTTP management UIs | Free / $5k+ support | Budget-conscious teams willing to customize |
| PrinterLogic Scanner Module | Proprietary OEM APIs + firmware checks | Custom quote | Organizations using HP, Canon, or Ricoh at scale |
| Manual Metasploit Modules | PostScript, PJL injection, memory leaks | Free | Red teams hunting zero-days |
Validate Findings with Manual Checks
Automated tools flag CVE-2021-3437—but does your specific firmware version actually expose it? Pull the printer’s config page. Check for open telnet shells or default credentials like “admin:1234.” Real exploits don’t care about CVSS scores.
The Industry Secret: Printers Are Now Attack Launchpads
Here’s what vendors won’t tell you: Printers with hard drives retain job logs, scanned images, and network credentials—even after “deletion.” A single unpatched Xerox WorkCentre running firmware from 2019 was used last year to exfiltrate 14GB of legal contracts via DNS tunneling through its embedded web server.
Think about it. Your SOC monitors endpoints, cloud apps, firewalls. But who’s watching the MFP that just initiated an outbound TLS connection to a Tor exit node in Kiev? Exactly. That’s why vulnerability scanning for printers must include behavioral baselining—not just CVE matching.
Frequently Asked Questions
Can printers really be hacked?
Yes. Printers run full OSes with known exploits. Attackers use them to pivot, exfiltrate data, or launch lateral movement. Ignoring them is like leaving a basement window unlocked.
How often should I scan my printers?
Quarterly at minimum—but integrate printer IPs into your continuous vulnerability management pipeline. Firmware updates can reintroduce flaws; new CVEs drop weekly.
Do home printers need scanning?
If it’s network-connected and handles sensitive documents (tax forms, resumes), yes. Home routers rarely segment IoT devices—so a compromised printer becomes a local spy.
