CVE-2026-84115 in Cleo Harmony: JWT Refresh Token Handler Flaw Exposes Remote Attack Risk

A critical vulnerability identified as CVE-2026-84115 affects Cleo Harmony versions through 5.8.1.10, with the weakness tied to the platform’s JWT Refresh Token Handler and the /api/connections endpoint. MITRE documented the issue on September 1, 2026, while VulDB classified it as a serious privilege-management vulnerability with a CVSS score of 8.3. CVE-2026-84115 Targets JWT Refresh Token Handler According to the vulnerability analysis , CVE-2026-84115 involves an unknown function within the JWT Refresh Token Handler component. …