What is CVE-2024-55956?
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.
The record classifies CVE-2024-55956 under weakness class CWE-77. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity, availability. 3 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 666 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 9.8 — CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS (FIRST)
- 93.9% probability of exploitation in the next 30 days, higher than 99.8% of all scored CVEs
- CISA KEV
- Listed since 2024-12-17, federal remediation deadline 2025-01-07 — used in known ransomware campaigns
- Threadlinqs priority
- 10/10 — CISA lists it as used in ransomware, which Threadlinqs scores at the maximum
- Published
- 2024-12-13, last modified 2026-08-05
Is CVE-2024-55956 being exploited?
CISA added CVE-2024-55956 to the Known Exploited Vulnerabilities catalog on 2024-12-17, which means the agency holds evidence of exploitation in the wild; US federal civilian agencies had to remediate it by 2025-01-07 under BOD 22-01. CISA flags the vulnerability as one used in known ransomware campaigns. Weaponised exploit code for CVE-2024-55956 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. A ProjectDiscovery Nuclei detection template exists (http/cves/2024/CVE-2024-55956.yaml). It currently carries a trending score of 50 in the Threadlinqs vulnerability feed.
- trickest/cve (trickest)
Affected products and versions
- Cleo: Harmony, Lexicom, Vltrader
How to fix CVE-2024-55956
Vendor advisory: https://support.cleo.com/hc/en-us/articles/28408134019735-Cleo-Product-Security-Advisory-CVE-Pending. Because CVE-2024-55956 is KEV-listed, US federal civilian agencies were required to apply the vendor fix, or stop using the product, by 2025-01-07. Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.
Threat activity tracking CVE-2024-55956
1 tracked threat in the Threadlinqs corpus references CVE-2024-55956, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, NVD, FIRST EPSS, CISA KEV, GitHub Security Advisories, public proof-of-concept repositories, ProjectDiscovery Nuclei. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.