CVE-2026-84115: Cleo Harmony JWT Refresh Token connections privileges management

Published Sep 1, 2026
·
Updated

A vulnerability was found in Cleo Harmony up to 5.8.1.10. The affected element is an unknown function of the file /api/connections of the component JWT Refresh Token Handler. Performing a manipulation of the argument Bearer results in improper privilege management. The attack is possible to be carried out remotely. The exploit has been made public and could be used. Upgrading to version 5.8.1.11 is sufficient to fix this issue. It is recommended to upgrade the affected component.

Affected Software

1 affected component
Cleo Harmony<=5.8.1.10

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Cleo Harmony to a version that resolves this vulnerability.

    Fixed in 5.8.1.11

Event History

Sep 1, 2026
CVE Published
via MITRE·03:00 PM
Data Sourced
via MITRE·03:00 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

Who can exploit this issue?

The issue can be exploited remotely without privileges or user interaction. Exploitation involves manipulating the Bearer argument handled by the JWT Refresh Token Handler on the /api/connections endpoint.

2

Which deployments are affected?

Cleo Harmony versions up to and including 5.8.1.10 are affected. Version 5.8.1.11 fixes the issue.

3

Is public exploit information available?

Yes. The exploit has been made public and could be used, increasing the likelihood of attempted exploitation.

Contact

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