CVE-2026-42082

LOW

free5GC: Missing Concurrent NAS SMC Validation During NGAP Handover

Title source: cna
STIX 2.1

Description

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, the AMF in Free5GC does not enforce the concurrent security procedure rules defined in 3GPP TS 33.501 §6.9.5.1. The AMF does not check for ongoing N2 handover procedures before initiating a NAS Security Mode Command, and vice versa. This can lead to mismatches between NAS and AS security contexts in the network and the UE. This vulnerability is fixed in 4.2.2.

References (1)

Core 1
Core References

Scores

CVSS v3 3.7
EPSS 0.0022
EPSS Percentile 12.5%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-358
Status published
Products (2)
free5gc/amf 0 - 1.4.3Go
free5gc/free5gc < 4.2.2 (2 CPE variants)
Published May 27, 2026
Tracked Since May 27, 2026