Cleo Harmony up to 5.8.1.10 JWT Refresh Token /api/connections Bearer privileges management

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.5$0-$5k1.36+

Summaryinfo

A vulnerability classified as critical was found in Cleo Harmony up to 5.8.1.10. The impacted element is an unknown function of the file /api/connections of the component JWT Refresh Token Handler. Executing a manipulation of the argument Bearer can lead to privileges management. This vulnerability appears as CVE-2026-84115. The attack may be performed from remote. In addition, an exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical was found in Cleo Harmony up to 5.8.1.10. This vulnerability affects an unknown function of the file /api/connections of the component JWT Refresh Token Handler. The manipulation of the argument Bearer with an unknown input leads to a privileges management vulnerability. The CWE definition for the vulnerability is CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. As an impact it is known to affect confidentiality, integrity, and availability.

The advisory is available at support.cleo.com. This vulnerability was named CVE-2026-84115. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details and also a public exploit are known. This vulnerability is assigned to T1068 by the MITRE ATT&CK project.

It is possible to download the exploit at support.cleo.com. It is declared as proof-of-concept.

Upgrading to version 5.8.1.11 eliminates this vulnerability. The upgrade is hosted for download at support.cleo.com.

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Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.3
VulDB Meta Temp Score: 7.5

VulDB Base Score: 8.3
VulDB Temp Score: 7.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Privileges management
CWE: CWE-269 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Harmony 5.8.1.11

Timelineinfo

09/01/2026 Advisory disclosed
09/01/2026 +0 days VulDB entry created
09/01/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: support.cleo.com
Status: Confirmed

CVE: CVE-2026-84115 (🔒)
GCVE (CVE): GCVE-0-2026-84115
GCVE (VulDB): GCVE-100-397558
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 09/01/2026 09:25
Changes: 09/01/2026 09:25 (58)
Complete: 🔍
Submitter: ilyass-armadin
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #882468: Cleo Harmony < 5.8.1.11 Privilege Escalation via Cross-Store Identity Lookup Confusion (by support.cleo.com)

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