CVE-2026-30080

OpenAirInterface v2.2.0 contains a security downgrade vulnerability in its 5G network authentication mechanism. The software improperly accepts Security Mode Complete messages without integrity protection, allowing User Equipment (UE) devices to register using the weaker IA0 algorithm instead of the supported NIA1 or NIA2 standards. This downgrade creates a security context vulnerability that could enable replay attacks against the network. The vulnerability carries a HIGH CVSS score of 7.5 with a network-based attack vector requiring no authentication, low attack complexity, and no user interaction. The primary impact is integrity compromise, as attackers could replay captured authentication messages to gain unauthorized network access. The EPSS score of 0.00032 indicates this is not a frequently targeted vulnerability in the current threat landscape. There is no evidence of active exploitation in the wild, as the vulnerability does not appear on the Known Exploited Vulnerabilities list and shows inactive status on security hotlists. No public exploit code is currently available, and community attention remains minimal. Organizations running OpenAirInterface v2.2.0 should prioritize patching to prevent potential replay-based authentication bypasses, particularly given the critical nature of 5G network security.