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.
Affected products
free5gc: free5gc
References2
- github.com/free5gc/free5gc/security/advisories/GHSA-vrrx-58h3-p… ExploitVendor Advisory
- github.com/free5gc/free5gc/security/advisories/GHSA-vrrx-58h3-p… ExploitVendor Advisory
Metrics
- CVSS 3.1
-
5.4
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L - EPSS — exploit probability
- 0% percentile: 17 · as of 14 November 2026
- CWE
- CWE-358
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