Unauthorized Access in free5GC 5G Core Network Implementation by free5GC

CVE-2026-44330

What is CVE-2026-44330?

The free5GC project, an open-source implementation of the 5G core network, contains a significant security flaw in its NEF (Network Exposure Function) component. Prior to version 4.2.2, the nnef-pfdmanagement route group was exposed without the necessary inbound OAuth2/bearer-token authorization. This weakness allows an attacker with access to the NEF on the Service-Based Interface (SBI) to exploit the system using a forged or arbitrary bearer token. Consequently, the attacker can retrieve PFD (Produced Data Format) application data through unsecured GET requests and manipulate subscriptions using unauthorized POST and DELETE methods. The vulnerability stems from the lack of appropriate authentication middleware for this route group, which is crucial as it is intended for production use, expected to be protected by the secure OAuth2 settings. The issue has been remediated in version 4.2.2.

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