CVE-2026-48558

CriticalActively exploited (CISA KEV)

Description

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.

SeverityCritical
CVSS10.0
Exploit probability—
ProductSimpleHelp SimpleHelp
PublishedJun 12, 2026
First seenJun 12, 2026
Added to KEVJun 29, 2026
Weakness typeCWE-347CWE-347

How to fix

CISA 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.

CISA due date: Jul 2, 2026
Update
  • simple-help simplehelp5.5.16 or later

Affected products

ProductAffected versionsFixed in
simple-help simplehelpv < 5.5.16, 6.05.5.16

Check your version

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