---
id: CVE-2026-44319
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, free5GC's NEF terminates the entire process when a stored
  PFD-subscription notifyUri cannot be reached. In
  PfdChangeNotifier.FlushNotifications(), the notif…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-20
  - CWE-617
  - CWE-755
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-2026-44319'
references:
  - url: 'https://github.com/free5gc/free5gc/issues/924'
    label: security-advisories@github.com
  - url: 'https://github.com/free5gc/free5gc/security/advisories/GHSA-rxrq-fv76-26pr'
    label: security-advisories@github.com
  - url: >-
      https://github.com/free5gc/nef/commit/f110517b1189801950b50668a593398687049074
    label: security-advisories@github.com
  - url: 'https://github.com/free5gc/nef/pull/25'
    label: security-advisories@github.com
  - url: 'https://github.com/free5gc/free5gc/issues/924'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: 'https://github.com/free5gc/free5gc/security/advisories/GHSA-rxrq-fv76-26pr'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00655
epssPercentile: 0.50202
ingestedAt: '2026-10-14T20:53:12.329Z'
---

## Overview

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF terminates the entire process when a stored PFD-subscription notifyUri cannot be reached. In PfdChangeNotifier.FlushNotifications(), the notifier calls NnefPFDmanagementNotify(...) and on any delivery error invokes logger.PFDManageLog.Fatal(err), which is os.Exit(1)-equivalent in Go. An attacker who can create a PFD subscription with an attacker-chosen notifyUri and then trigger a PFD change can deterministically kill NEF on the asynchronous delivery attempt -- the process exits with status 1, dropping NEF's entire SBI surface until restart. This vulnerability is fixed in 4.2.2.

## Affected

- `free5gc < 4.2.2`

## Remediation

Upgrade past the affected range:

- `free5gc 4.2.2`