Vulnerability · Published May 27, 2026 · Assigned by GitHub_M

CVE-2026-42082free5GC: Missing Concurrent NAS SMC Validation During NGAP Handover

Low 3.7

In plain English

A low-severity security flaw in free5gc from free5gc. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 17% of all known vulnerabilities).

Severity (CVSS 3.1)3.7Low

Exploit odds (30 days)0.3%top 83.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official 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 packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/free5gc/amf	no fix listed	GHSA-vrrx-58h3-prmh
Go	github.com/free5gc/amf	no fix listed	GO-2026-5673

Affected products (as reported)

Vendor	Product	Versions
free5gc	free5gc	< 4.2.2

Weakness: CWE-358 · Vector: CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L

References

https://github.com/free5gc/free5gc/security/advisories/GHSA-vrrx-58h3-prmh x_refsource_CONFIRM