---
id: CVE-2026-42459
title: free5GC is an open-source implementation of the 5G core network
summary: >-
  free5GC is an open-source implementation of the 5G core network. Prior to
  4.2.2, the free5GC UDM component fails to validate the supi path parameter in
  six GET handlers of the nudm-sdm (Subscriber Data Management) service. An
  unauthentic…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-20
  - CWE-209
vendor: free5gc
product: free5gc
affected:
  - free5gc < 4.2.2
patched:
  - free5gc 4.2.2
published: '2026-05-27'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T20:10:00.190'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-42459'
references:
  - url: 'https://github.com/free5gc/free5gc/security/advisories/GHSA-585v-hcgf-jhfr'
    label: security-advisories@github.com
  - url: 'https://github.com/free5gc/free5gc/security/advisories/GHSA-585v-hcgf-jhfr'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00448
epssPercentile: 0.37391
ingestedAt: '2026-10-14T20:53:12.328Z'
---

## Overview

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, the free5GC UDM component fails to validate the supi path parameter in six GET handlers of the nudm-sdm (Subscriber Data Management) service. An unauthenticated attacker can inject control characters into the SUPI parameter, causing UDM to forward a malformed request to UDR and return a 500 Internal Server Error response that exposes internal infrastructure details. This vulnerability is fixed in 4.2.2.

## Affected

- `free5gc < 4.2.2`

## Remediation

Upgrade past the affected range:

- `free5gc 4.2.2`