CVE-2026-48558
SimpleHelp Authentication Bypass via Missing OIDC JWT Signature Verification
KEVCRITICAL 9.5EPSS 5.7%
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
- SimpleHelp
- CVSS v4.0 VULNCHECK
- 9.5 CRITICAL
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:X/V:X/RE:X/U:X - CVSS v3.1 VULNCHECK
- 10.0 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - EPSS
- 5.72% chance of exploitation in the next 30 days, 93rd percentile
- CISA KEV
- added 2026-06-29
- Nuclei
- critical · CWE-347
- Published
- 2026-06-12
- Updated
- 2026-10-07
Proof-of-concept exploits (2)
- https://horizon3.ai/attack-research/disclosures/cve-2026-48558-simplehelp-authentication-…
- J4ck3LSyN-Gen2/CVE-2026-485587★ · 2026-07-02
Nuclei templates (1)
Metasploit modules (1)
Security advisories
- https://simple-help.com/security/simplehelp-security-update-2026-05
- https://blackpointcyber.com/blog/a-djinn-in-the-machine-taskweavers-node-js-intrusion-cha…
- https://horizon3.ai/attack-research/disclosures/cve-2026-48558-simplehelp-authentication-…
- https://simple-help.com/release-news