CVE-2026-48558
CRITICALCVE-2026-48558 is a critical-severity (CVSS 10) CWE-347 vulnerability. It is in CISA's Known Exploited Vulnerabilities catalog (added 2026-06-29) — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.
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,…
Exploitation Status
Actively exploited in the wild
- Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2026-06-29. Federal agencies were required to remediate by 2026-07-02.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2026-48558.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-48558 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 379,842 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
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.
Affected Products
simplehelpsimple-helpResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
VulnerabilityDetect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Remediation status
No fixed release is recorded for CVE-2026-48558 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.
Mitigate without a patch
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
How to detect CVE-2026-48558
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2026-48558 -u https://target- Template
- SimpleHelp <=5.5.15 - OIDC JWT Authentication Bypass
- Severity
- critical
- Impact
- Remote attackers can bypass authentication and multi-factor authentication to gain full technician access.
- Remediation
- Update to a version later than 5.5.15 or the final 6.0 release.
Template by ProjectDiscovery nuclei-templates (0x_Akoko, pdteam), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2026-48558 in your dependencies?
Find it across , including transitive dependencies.