In OpenAirInterface V2.2.0 AMF, Out of sequence messages causes incorrect state transition during UE registration procedure.
Date: 2026-04
Affected: openairinterface/oai-cn5g-amf
Attack vector: other
Category: vulnerability-disclosure
Severity: Critical
CVE: CVE-2026-30079
CWE: CWE-288
CVSS: 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

In OpenAirInterface V2.2.0 AMF, Out of sequence messages causes incorrect state transition during UE registration procedure. This allows authentication to be bypassed completely. If a SecurityModeComplete message is sent after InitialUERegistration, a registration reject is received followed by a registration accept! This leads the UE to be registered without proper authentication.


Mitigations:

Architectural layers (MAESTRO):