CVE-2024-50623 Cleo Multiple Products Unrestricted File Upload Vulnerability
Cleo Harmony, VLTrader, and LexiCom, which are managed file transfer products, contain an unrestricted file upload and download vulnerability that can lead to remote code execution with elevated privileges.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 13 Dec 2024.
- CISA lists it as known to be used in ransomware campaigns.
- Rated Critical severity (CVSS 9.8, scored by CISA).
- It has been in the catalogue for 693 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
In Cleo Harmony before 5.8.0.21, VLTrader before 5.8.0.21, and LexiCom before 5.8.0.21, there is an unrestricted file upload and download that could lead to remote code execution.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Cleo Multiple Products. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Vulnerability Management - 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
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