Exploited vulnerabilities / CVE-2026-48558
Confirmed exploited · authentication bypass · SimpleHelpCVE-2026-48558
SimpleHelp authentication bypass, confirmed exploited in the wild.
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's name for it | SimpleHelp Authentication Bypass Vulnerability |
|---|---|
| Vendor and product | SimpleHelp · SimpleHelp |
| Type | authentication bypass · CWE-347 |
| Exploited | Confirmed by CISA listed 29 June 2026 |
| Likelihood | one of the most likely to be exploited of every vulnerability tracked |
| Deadline | 2 July 2026 · already passed |
| Used in ransomware | Not reported |
| Advisories | simple-help.com ↗ · www.cisa.gov ↗ · www.cisa.gov ↗ · nvd.nist.gov ↗ |
Three steps, in this order
Apply the vendor fix and restart the affected service.
Put the login or management interface behind a VPN or allow-list; a bypass makes passwords irrelevant.
Rotate credentials and session keys the product holds, and review accounts and configuration changes since the listing date.
| CISA's 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. |
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CVE-2026-48558 in short
Is CVE-2026-48558 being exploited?
Yes. CISA added CVE-2026-48558 to its Known Exploited Vulnerabilities catalogue on 29 June 2026, which it does only on evidence of exploitation in the wild.
What is the CISA deadline for CVE-2026-48558?
US federal agencies must remediate it by 2 July 2026. Everyone else should treat that date as the latest safe point to patch an internet-facing system.
How likely is CVE-2026-48558 to be exploited in the next 30 days?
FIRST's Exploit Prediction Scoring System gives it 80%, the 99th percentile of every CVE it scores.
How do I fix CVE-2026-48558?
Apply the vendor fix and restart the affected service. Put the login or management interface behind a VPN or allow-list; a bypass makes passwords irrelevant. Rotate credentials and session keys the product holds, and review accounts and configuration changes since the listing date.
Other SimpleHelp vulnerabilities being exploited
| CVE | Product | Type | Listed |
|---|---|---|---|
| CVE-2024-57728 | SimpleHelp | remote code execution | 24 April 2026 |
| CVE-2024-57726 | SimpleHelp | privilege escalation | 24 April 2026 |
Sources: CISA Known Exploited Vulnerabilities catalogue (released 10 November 2026) and FIRST EPSS. Page compiled automatically by SAK T.L.M, the threat-intelligence tool of SAK T.E.C, on 13 November 2026.