CVE-2026-48558 — Simplehelp
CRITICALCVE-2026-48558 is a critical-severity (CVSS 10) CWE-347 vulnerability in simple-help simplehelp. It is in CISA's Known Exploited Vulnerabilities catalog (added 2026-06-29) — treat it as actively exploited and patch now. A fix is available — see the affected versions and patch details 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
Where this sits among everything scored
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
Vendor / applianceDetect
Inventory every simple-help simplehelp deployment and check each version against the affected-products list above.
Fix
Apply the simple-help simplehelp security patch or hotfix for CVE-2026-48558 on the affected version, following the vendor advisory for your exact build.
Workarounds
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. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
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 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.