CVE-2026-84115: Improper Privilege Management in Cleo Harmony
Description
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.
CVSS v4.0
Score 6.9medium
Affected software
Cleo
Harmony
cpe:2.3:a:cleo:harmony:*:*:*:*:*:*:*:*AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability affects Cleo Harmony versions up to 5.8.1.10 in the JWT Refresh Token Handler component at the /api/connections endpoint. Improper handling of the Bearer argument allows an attacker to manipulate privileges improperly. The attack vector is remote and does not require prior authentication or user interaction. A public exploit exists. The vendor has released version 5.8.1.11 which fixes this issue.
Potential Impact
Successful exploitation could allow an unauthenticated remote attacker to gain improper privileges due to flawed privilege management in the JWT Refresh Token Handler. This could lead to unauthorized access or actions within the affected system. The CVSS 4.0 base score is 6.9 (medium severity), reflecting network attack vector, low complexity, no privileges or user interaction required, and limited confidentiality, integrity, and availability impacts.
Mitigation Recommendations
Upgrade Cleo Harmony to version 5.8.1.11 or later to remediate this vulnerability. This upgrade addresses the improper privilege management issue. No other mitigations are indicated or required according to the available data.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulDB
- Date Reserved
- 2026-09-01T07:20:41.146Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a96edc2acd9273b49deccd4
Added to database: 09/01/2026, 15:22:42 UTC
Last enriched: 09/07/2026, 14:42:50 UTC
Last updated: 10/16/2026, 06:48:19 UTC
Views: 140
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