CVE-2023-50736
📋 TL;DR
A memory corruption vulnerability in the PostScript interpreter of Lexmark devices allows attackers to execute arbitrary code. This affects various Lexmark printer and multifunction devices when processing malicious PostScript files. Organizations using vulnerable Lexmark devices are at risk.
💻 Affected Systems
- Various Lexmark printers and multifunction devices
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Full device compromise allowing attacker to install persistent malware, steal data, pivot to internal networks, or disrupt printing services.
Likely Case
Printer compromise leading to service disruption, data exfiltration from print jobs, or use as internal network foothold.
If Mitigated
Limited impact with network segmentation and proper access controls preventing exploitation attempts.
🎯 Exploit Status
Requires sending malicious PostScript file to vulnerable device. No public exploit code known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware updates specified in Lexmark security advisory
Vendor Advisory: https://www.lexmark.com/en_us/solutions/security/lexmark-security-advisories.html
Restart Required: Yes
Instructions:
1. Visit Lexmark security advisory page. 2. Identify affected device models. 3. Download latest firmware for your device. 4. Apply firmware update following manufacturer instructions. 5. Verify update completed successfully.
🔧 Temporary Workarounds
Disable PostScript processing
allDisable PostScript interpreter if not required for business operations
Network segmentation
allIsolate printers on separate VLAN with restricted access
🧯 If You Can't Patch
- Implement strict network access controls to limit printer access to trusted hosts only
- Monitor for suspicious print jobs and PostScript processing attempts
🔍 How to Verify
Check if Vulnerable:
Check device model and firmware version against Lexmark advisory listCheck Version:
Check printer web interface or control panel for firmware versionVerify Fix Applied:
Verify firmware version matches patched version in advisory and test PostScript functionality📡 Detection & Monitoring
Log Indicators:
- Failed PostScript processing attempts
- Unusual print job sources
- Firmware modification alerts
Network Indicators:
- Unexpected PostScript file transfers to printers
- Printer communication with suspicious external IPs
SIEM Query:
source="printer_logs" AND (event="postscript_error" OR event="firmware_change")