CVE-2026-44330
CWE-863Published: May 27, 2026· Updated: May 28, 2026
Official Description
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-pfdmanagement route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can use a forged or arbitrary bearer token (e.g. Authorization: Bearer not-a-real-token) to read PFD application data via GET /applications and GET /applications/{appID}, and to create or delete PFD change-notification subscriptions via POST /subscriptions and DELETE /subscriptions/{subID}. Same root cause as the other NEF SBI findings: the route group is mounted without any inbound auth middleware. Unlike the OAM and traffic-influence groups, nnef-pfdmanagement IS declared in the runtime ServiceList, so this is the production-intended path that operators expect to be protected by OAuth2 setting receive from NRF: true -- and it is not. This vulnerability is fixed in 4.2.2.
Risk Analysis
A critical vulnerability in free5GC's NEF component allows a network attacker to bypass authorization and access PFD management functionalities. This flaw enables unauthorized reading of PFD application data and creation or deletion of PFD change-notification subscriptions using a forged or arbitrary bearer token. The CVSS score of 10.0 signifies the highest level of severity.
No public exploits are currently known for this vulnerability. The flaw is remotely exploitable with low attack complexity, indicating that an attacker could potentially exploit it over a network with minimal effort.
Upgrade free5GC to version 4.2.2 or later to fix this authorization bypass. Ensure all NEF routes are properly secured with OAuth2/bearer-token authorization middleware.
Technical Analysis
CVE-2026-44330 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 10.0.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (2)
Quick Facts
Related CVEs (CWE-863)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-44330 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts