CVE-2026-44326

CRITICAL

free5GC: NEF 3gpp-traffic-influence API is unauthenticated; missing or forged bearer tokens can create, read, patch, and delete subscriptions

Title source: cna
STIX 2.1

Description

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-traffic-influence API without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can create, read, patch, and delete traffic-influence subscriptions either with no Authorization header at all, or with a forged bearer token (e.g. Authorization: Bearer not-a-real-token). This includes creating AnyUeInd=true subscriptions intended to affect group / any-UE traffic steering. The route group is also reachable even when the running config's ServiceList does not declare it, so operators who think they disabled the service via config are still exposed. This vulnerability is fixed in 4.2.2.

References (3)

Core 3
Core References
X_Refsource_Misc x_refsource_misc
https://github.com/free5gc/free5gc/issues/859
X_Refsource_Misc x_refsource_misc
https://github.com/free5gc/nef/pull/23

Scores

CVSS v3 9.4
EPSS 0.0029
EPSS Percentile 20.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-862
Status published
Products (2)
free5gc/free5gc < 4.2.2 (2 CPE variants)
free5gc/nef 0 - 1.2.3Go
Published May 27, 2026
Tracked Since May 27, 2026