Threats / Cleo / CVE-2024-55956
CVE-2024-55956
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Cleo Multiple Products vulnerability
Cleo managed file transfer products contain an unrestricted file upload vulnerability allowing unauthenticated attackers to execute arbitrary commands via the Autorun directory.
Verdict
Today item, not a backlog item.
An unauthenticated attacker can upload malicious bash or PowerShell scripts to a default Autorun directory, achieving remote code execution on the host system without authentication. This vulnerability is actively exploited in ransomware campaigns.
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
43 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2024-12-17), flagged for known ransomware use.
Probability (EPSS)
EPSS 0.93804 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Cleo, Multiple Products. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-276 Incorrect Default Permissions — weakness family: Authorization / access control.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I upload a malicious script file to the Autorun directory without authentication.
Business
The organization's file transfer infrastructure is compromised without requiring valid credentials.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I leverage default Autorun settings to execute my uploaded bash or PowerShell commands automatically.
Business
Arbitrary code runs with the privileges of the Cleo service, potentially system-level access.
3
Lateral reach — past segmentation narrative 3
Attacker
I establish persistent command execution and lateral movement within the network.
Business
Attackers gain foothold for ransomware deployment, data exfiltration, and infrastructure compromise.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05