cbcvebase.
CVE-2026-48558
published 2026-06-12

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…

PriorityP198critical10CVSS 3.1
AVNACLPRNUINSCCHIHAH
KEVITW
CISA Known Exploited Vulnerabilitydue 2026-07-02
Exploited in the wild
EPSS
1.22%
64.9th percentile
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

4 ranges
VendorProductVersion rangeFixed in
simple-helpsimplehelp< 5.5.165.5.16
simple-helpsimplehelp
simplehelpsimplehelp>= 5.5.0 < 5.5.165.5.16
simplehelpsimplehelp>= 6.0 < 6.0 RC26.0 RC2

Detection & IOCsextracted from sources · hover to see the quote

domaina.dev-tunnels[.]com
ip96.126.130[.]126
port58942
  • Hunt for new authenticated Technician accounts with unknown or suspicious names and/or email addresses — these are a primary indicator of CVE-2026-48558 exploitation.
  • Detect TaskWeaver loader activity by monitoring for node.exe executing a file named jquery.js — a masquerading technique used to blend in with legitimate JavaScript libraries.
  • Monitor for outbound encrypted connections from managed endpoints to 'a.dev-tunnels[.]com', used by TaskWeaver as its C2 channel.
  • Monitor for outbound connections to 96.126.130[.]126 on port 58942, used for exfiltration of TAR/GZIP/AES-256-GCM encrypted data by Djinn Stealer.
  • On Linux endpoints managed by SimpleHelp, alert on processes reading /proc/<pid>/cmdline and /proc/<pid>/environ in bulk, indicative of Djinn Stealer credential harvesting.
  • ·CVE-2026-48558 only affects SimpleHelp servers with OIDC authentication configured (generic OIDC or Azure AD OIDC); servers using other authentication methods are not vulnerable.
  • ·MFA enforcement does not mitigate this vulnerability — on first login, the attacker-controlled Technician account can self-register its own MFA method, bypassing the control entirely.
  • ·If patching to 5.5.16 / 6.0RC2 is not immediately possible, restricting technician login sources via IP-based allowlists is a documented interim mitigation.

CVSS provenance

nvdv3.110.0CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
nvdv4.09.5CRITICALCVSS: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
vulncheck10.0CRITICAL
cisa10.0CRITICAL
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