CVE-2024-55956
Cleo Multiple Products Unauthenticated File Upload Vulnerability
Cleo Multiple Products
In Cleo Harmony before 5.8.0.24, VLTrader before 5.8.0.24, and LexiCom before 5.8.0.24, an unauthenticated user can import and execute arbitrary Bash or PowerShell commands on the host system by leveraging the default settings of the Autorun directory.
Ransomware groups exploiting CVE-2024-55956
The ransomware group known as Cl0p is a variant of a previously known strain dubbed CryptoMix. It is worth noting that this variant was delivered as the final payload in a phishing campaign in 2019 and was exclusively financially motivated, with attacks carrie
Exploitation is attributed to these groups across their recorded activity. It does not follow that every organisation they listed was reached through CVE-2024-55956 — the source data does not record an entry point per incident.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 17 December 2024. US federal agencies were required to remediate it by 7 January 2025. CISA records this vulnerability as known to be used in ransomware campaigns.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 93.8%, which is higher than 99.8% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Recent listings by these groups
Disclosures from the groups above, newest first.
Frequently asked questions
Is CVE-2024-55956 being exploited by ransomware groups?
Yes. CVE-2024-55956 is recorded as exploited by Clop. Between them these groups account for 783 victim disclosures in this database. CISA also records this vulnerability as used in ransomware campaigns.
What does CVE-2024-55956 affect?
CVE-2024-55956 affects Cleo Multiple Products. In Cleo Harmony before 5.8.0.24, VLTrader before 5.8.0.24, and LexiCom before 5.8.0.24, an unauthenticated user can import and execute arbitrary Bash or PowerShell commands on the host system by leveraging the default settings of the Autorun directory.
How severe is CVE-2024-55956?
CVE-2024-55956 is rated CRITICAL with a CVSS base score of 9.8. EPSS puts the probability of exploitation in the next 30 days at 93.8%, higher than 99.8% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 7 January 2025.
How should organisations respond to CVE-2024-55956?
Apply the vendor patch for Cleo Multiple Products as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.