CVE-2026-48558
CRITICALCISA KEVEPSS 96th pctlDescription
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.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Exploit Intelligence
Very high risk: more likely to be exploited than 96% of all known CVEs.
Remediation due: 2026-07-02
References
Related Vulnerabilities
Other CWE-347 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2018-16042 | Medium | 6.5 | 82% | - | - |
| CVE-2025-25292 | Critical | 9.8 | 65% | - | Fix |
| CVE-2025-59718 | Critical | 9.8 | 63% | KEV | Fix |
| CVE-2021-22160 | Critical | 9.8 | 53% | - | Fix |
| CVE-2013-3900 | Medium | 5.5 | 45% | KEV | - |
| CVE-2018-0114 | High | 7.5 | 43% | - | Fix |
Common questions
How do I fix CVE-2026-48558?
Upgrade simplehelp to 5.5.16 or later.
Is CVE-2026-48558 being actively exploited?
Yes. CVE-2026-48558 is listed in the CISA Known Exploited Vulnerabilities catalog, which means exploitation has been observed in the wild. US federal agencies were required to remediate it by 2026-07-02. Treat it as a priority whatever its CVSS score says.
How severe is CVE-2026-48558?
CVE-2026-48558 has a CVSS v3 base score of 10.0, rated critical. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2026-48558 affect?
Published advisories record a fix for simplehelp (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2026-48558
Markdown
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-30.