Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since June 29, 2026.
CVE-2026-48558
SimpleHelp Authentication Bypass Vulnerability
Added to KEV June 29, 2026
Alert details
- Source feed
- CISA KEV
- CVE ID
- CVE-2026-48558
- CWE
- CWE-347
- Affected products
- SimpleHelp · SimpleHelp SimpleHelp
What happened
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.
What it means for your business
SimpleHelp SimpleHelp is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2026-48558). 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. CISA remediation due date: 2026-07-02. PremierePC tracks KEV alerts for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
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: July 2, 2026
Sources
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