Actively exploited in the wild
SimpleHelp Authentication Bypass Vulnerability
SimpleHelp — SimpleHelp · Listed in the CISA KEV since 2026-06-29. This indicates confirmed attacks in production environments.
Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CVE-2026-48558
CriticalCVSS 10.0KEVExploitation Probability (EPSS)
Elevated risk65th percentile — higher than 65% of all known CVEs
Summary
SimpleHelp versions 5.5.15 and prior and 6.0 pre-release versions contain an authentication bypass vulnerability in the OIDC authentication flow. Identity tokens submitted during login are accepted without verifying their cryptographic signature, allowing a remote, unauthenticated attacker to obtain a fully authenticated technician session.
Risk Assessment
An attacker can impersonate any user, gaining full access to the SimpleHelp system, potentially leading to data theft, remote session hijacking, and bypass of multi-factor authentication.
Recommendation
Immediately upgrade SimpleHelp to version 5.5.16 or later (or a stable 6.0 release) and verify that the OIDC configuration enforces token signature verification.
Original NVD description (English source)
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 vulnerable configuration, a remote, unauthenticated attacker can submit a forged token containing arbitrary identity claims to obtain a fully authenticated technician session. In some configurations, this may also allow bypass of multi-factor authentication. No user interaction is required.