PatchSiren cyber security CVE debrief
CVE-2026-48558 SimpleHelp CVE debrief
CVE-2026-48558 is a critical authentication bypass vulnerability in SimpleHelp versions 5.5.15 and prior and 6.0 pre-release versions. The vulnerability exists in the OIDC authentication flow, where identity tokens submitted during login are accepted without verifying their cryptographic signature. This allows a remote, unauthenticated attacker to 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.
- Vendor
- SimpleHelp
- Product
- Unknown
- CVSS
- CRITICAL 9.5
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-06-12
- Original CVE updated
- 2026-06-12
- Advisory published
- 2026-06-12
- Advisory updated
- 2026-06-12
Who should care
Administrators and users of SimpleHelp versions 5.5.15 and prior and 6.0 pre-release versions should be aware of this vulnerability and take immediate action to mitigate the risk.
Technical summary
The vulnerability has a CVSS score of 9.5 and is classified as CRITICAL. The CVSS vector is 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.
Defensive priority
HIGH
Recommended defensive actions
- Update SimpleHelp to a version that fixes the authentication bypass vulnerability.
- Review and update OIDC authentication configurations to ensure cryptographic signature verification is enabled.
- Implement additional security measures, such as multi-factor authentication, to reduce the risk of exploitation.
Evidence notes
The vendor of the affected product is currently listed as Unknown Vendor. However, based on the provided evidence, the vendor is likely SimpleHelp. The CVE record and NVD detail can be found at [cve-org] and [nvd], respectively. Additional information can be found at [ref-4], [ref-5], and [ref-6].
Official resources
CVE-2026-48558 was published on 2026-06-12T18:16:35.317Z and has not been modified since then.