SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-44330

A network attacker who can reach NEF on the SBI can use a forged or arbitrary bearer token (e.g.

CRITICAL 10.0EPSS 0.29%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.29%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
10.0 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:H
EPSS
0.29% probability · 21th percentile
CISA KEV
Not listed
Weakness
CWE-863
Affected
free5gc/free5gc
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.