CVE WatchJun 30, 2026

CVE-2026-48558

SimpleHelp Authentication Bypass Vulnerability

CVSS

10.0

Critical

EPSS

12.4%

p96

KEV

YES

Jun 29, 2026

Exploit Today

0-100

Published: Jun 12, 2026 · Last modified: Jun 30, 2026 · CWE-347

EPSS · 30d

11.5%EPSS · 30 days12.4%

2026-08-022026-08-31

KEV catalog record

Product

SimpleHelp / SimpleHelp

Vulnerability

SimpleHelp Authentication Bypass Vulnerability

Added to KEV

Jun 29, 2026

Remediate by

Jul 2, 2026

Known ransomware use

Summary description

SimpleHelp contains 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.

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.

Notes

https://simple-help.com/security/simplehelp-security-update-2026-05 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-48558

Technical 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.

Official references

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