CVE-2026-48558: CRITICAL (CVSS 10.0), Actively Exploited (CISA KEV)

CRITICAL (CVSS 10.0), Actively Exploited (CISA KEV), EPSS 1.2%. SimpleHelp versions 5.5.15 and prior and 6.0 pre-release versions contain an authentication bypass vulnerability in the OIDC authentication flow. When OIDC authentication is configured, identity tokens submitted during login are accepted without verifying their cryptographic signature. In a vulnerab