- Critical 9.5
- Known exploited (CISA KEV)
CVE-2026-48558
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.
Scores
The facts
- Published
- 12 June 2026
- Last changed
- 7 October 2026
- NVD status
- Analyzed
- Severity
- Critical, CVSS 9.5 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R… - Weakness
- Affects
- simple-help simplehelp
- Known exploited
- Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 29 June 2026.
- EPSS
- 5.7% chance of exploitation activity in the next 30 days (percentile 93).
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