CVE-2021-42637
📋 TL;DR
This Server Side Request Forgery (SSRF) vulnerability in PrinterLogic Web Stack allows attackers to use user-controlled input to craft URLs, potentially accessing internal systems and services. It affects all PrinterLogic Web Stack versions 19.1.1.13 SP9 and below. Organizations using vulnerable PrinterLogic deployments are at risk of internal network compromise.
💻 Affected Systems
- PrinterLogic Web Stack
📦 What is this software?
Web Stack by Printerlogic
Web Stack by Printerlogic
Web Stack by Printerlogic
Web Stack by Printerlogic
Web Stack by Printerlogic
⚠️ Risk & Real-World Impact
Worst Case
Attackers could pivot from the PrinterLogic server to access internal systems, steal sensitive data, execute remote code on internal servers, or perform lateral movement across the network.
Likely Case
Attackers scan and access internal services, retrieve metadata from cloud instances, or interact with internal APIs to gather information or perform limited actions.
If Mitigated
With proper network segmentation and egress filtering, impact is limited to the PrinterLogic server itself or adjacent systems in the same security zone.
🎯 Exploit Status
SSRF vulnerabilities are commonly weaponized. While no public PoC exists, the vulnerability is straightforward to exploit given the CVSS score of 9.8.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 19.1.1.13 SP9
Vendor Advisory: https://www.printerlogic.com/security-bulletin/
Restart Required: Yes
Instructions:
1. Download latest PrinterLogic Web Stack version from vendor portal. 2. Backup current configuration. 3. Install update following vendor instructions. 4. Restart PrinterLogic services. 5. Verify functionality.
🔧 Temporary Workarounds
Network Segmentation
allIsolate PrinterLogic server from sensitive internal networks using firewall rules
Input Validation
allImplement web application firewall rules to block SSRF patterns
🧯 If You Can't Patch
- Implement strict network egress filtering from PrinterLogic server to only allow necessary outbound connections
- Deploy web application firewall with SSRF protection rules in front of PrinterLogic
🔍 How to Verify
Check if Vulnerable:
Check PrinterLogic Web Stack version in admin interface. If version is 19.1.1.13 SP9 or earlier, system is vulnerable.Check Version:
Check PrinterLogic admin dashboard or run: Get-PrinterLogicVersion (Windows) or check /opt/printerlogic/version (Linux)Verify Fix Applied:
Verify version is newer than 19.1.1.13 SP9 in admin interface and test SSRF payloads no longer work.📡 Detection & Monitoring
Log Indicators:
- Unusual outbound HTTP requests from PrinterLogic server
- Requests to internal IP addresses from web interface
- URL patterns with internal network addresses
Network Indicators:
- PrinterLogic server making unexpected outbound connections
- HTTP requests to internal services from PrinterLogic IP
SIEM Query:
source="printerlogic" AND (url="*://10.*" OR url="*://192.168.*" OR url="*://172.16.*" OR url="*://127.*" OR url="*://localhost*")🔗 References
- http://printerlogic.com
- https://portswigger.net/daily-swig/printerlogic-vendor-addresses-triple-rce-threat-against-all-connected-endpoints
- https://securityaffairs.co/wordpress/127194/security/printerlogic-printer-management-suite-flaws.html
- https://thecyberthrone.in/2022/01/26/printerlogic-%F0%9F%96%A8-fixes-critical-vulnerabilities-in-its-suite/?utm_source=rss&utm_medium=rss&utm_campaign=printerlogic-%25f0%259f%2596%25a8-fixes-critical-vulnerabilities-in-its-suite
- https://www.printerlogic.com/security-bulletin/
- https://www.securityweek.com/printerlogic-patches-code-execution-flaws-printer-management-suite
- https://www.yahooinc.com/paranoids/paranoids-vulnerability-research-printerlogic-issues-security-alert/
- http://printerlogic.com
- https://portswigger.net/daily-swig/printerlogic-vendor-addresses-triple-rce-threat-against-all-connected-endpoints
- https://securityaffairs.co/wordpress/127194/security/printerlogic-printer-management-suite-flaws.html
- https://thecyberthrone.in/2022/01/26/printerlogic-%F0%9F%96%A8-fixes-critical-vulnerabilities-in-its-suite/?utm_source=rss&utm_medium=rss&utm_campaign=printerlogic-%25f0%259f%2596%25a8-fixes-critical-vulnerabilities-in-its-suite
- https://www.printerlogic.com/security-bulletin/
- https://www.securityweek.com/printerlogic-patches-code-execution-flaws-printer-management-suite
- https://www.yahooinc.com/paranoids/paranoids-vulnerability-research-printerlogic-issues-security-alert/
