Free5GC AMF has Missing Concurrent NAS SMC Validation During NGAP Handover

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

3.7 · CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L

EPSS

• CVE-2026-42082: 0.25% estimated exploitation activity in the next 30 days; percentile 16.54 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary The AMF in Free5GC v4.2.1 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. Details Vulnerability Type: CWE-358 (Improperly Implemented Security Check for Standard) Affected File: internal/ngap/handler.go — handleHandoverRequiredMain() and internal/gmm/sm.go — SecurityMode() Root Cause: 3GPP TS 33.501 §6.9.5.1 states: "Concurrent runs of security procedures may, in certain situations, lead to mismatches between security contexts in the network and the UE. In order to avoid such mismatches, the following rules shall be adhered to: 1. AMF shall not initiate any of the N2 procedures including a new key towards a UE if a NAS Security Mode Command procedure is ongoing with the UE. 2. The AMF shall not initiate a NAS Security Mode…

Published by the source

7 May 2026, 01:56 UTC

Last modified by the source

8 Jun 2026, 23:46 UTC

Source last checked

26 Oct 2026, 15:23 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-vrrx-58h3-prmh

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-42082

Advisory: Free5GC AMF has Missing Concurrent NAS SMC Validation During NGAP Handover
IDs: CVE-2026-42082, GHSA-vrrx-58h3-prmh
Record: https://patchnext.com/advisories/cve-2026-42082 (revision 1, source checked 26 Oct 2026, 15:23 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 3.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/free5gc/amf: affected <= 1.4.3

## Suggested inspection (read-only)
- Go github.com/free5gc/amf: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/free5gc/amf.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-vrrx-58h3-prmh (GitHub-reviewed advisory GHSA-vrrx-58h3-prmh lists affected ranges: Go github.com/free5gc/amf >=0 <=1.4.3)

Commands are suggestions: review each one before running it.