Known exploited · Cleo
CVE-2024-55956: Cleo Multiple Products Unauthenticated File Upload Vulnerability
What it is
Cleo Harmony, VLTrader, and LexiCom, which are managed file transfer products, contain an unrestricted file upload vulnerability that could allow an unauthenticated user to import and execute arbitrary bash or PowerShell commands on the host system by leveraging the default settings of the Autorun directory.
- Vendor
- Cleo
- Product
- Multiple Products
- Added to KEV
- December 17, 2024
- CISA due date
- January 7, 2025
- Ransomware use
- Known
What CISA requires
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Forensic triage
No
What to do now
- Find every instance of Multiple Products you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before January 7, 2025 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.