Cyber Resilience

CVE-2026-30080

Auth Bypass in Openairinterface Oai-Cn5G-Amf 2.2.0

Public PoCAuth Bypass
Published
08 April 2026
Modified
25 July 2026
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS Score 0.0025 17th percentile
Risk Priority 56 floored blend · peak EPSS

Summary

CVE-2026-30080 is a high-severity Authentication Bypass by Capture-replay (CWE-294) vulnerability in Openairinterface Oai-Cn5G-Amf. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Network Sniffing (T1040); ranked at the 17th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SC-23 (Session Authenticity) and SC-8 (Transmission Confidentiality and Integrity) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-30080 is a vulnerability in OpenAirInterface version 2.2.0, specifically within the CN5G AMF (Access and Mobility Management Function) component. The issue arises because the software accepts a Security Mode Complete message without any integrity protection, even though its configuration supports integrity algorithms NIA1 and NIA2. If a UE (User Equipment) sends an initial registration request advertising only the IA0 security capability (indicating no integrity), OpenAirInterface accepts it and proceeds, establishing a downgraded security context. This flaw is classified under CWE-294 and carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N).

An unauthenticated remote attacker can exploit this vulnerability by impersonating a UE and transmitting an initial registration request limited to IA0 integrity capability. With network accessibility, low attack complexity, and no required privileges or user interaction, the attacker tricks the AMF into activating a security context devoid of integrity protection. This enables replay attacks, where malicious messages can be captured and resent, resulting in high integrity impacts such as unauthorized modifications or repetitions of critical signaling messages.

The vulnerability is tracked in a GitLab issue for the oai-cn5g-amf repository at https://gitlab.eurecom.fr/oai/cn5g/oai-cn5g-amf/-/issues/78, where security practitioners can review details on potential mitigations, patches, or workarounds.

OWASP Top 10 for Web (2025)

A07:2025 Authentication Failures

EU & UK References

Vulnerability Data

OpenAirInterface v2.2.0 accepts Security Mode Complete without any integrity protection. Configuration has supported integrity NIA1 and NIA2. But if an UE sends initial registration request with only security capability IA0, OpenAirInterface accepts and proceeds. This downgrade security context can lead…

more

to the possibility of replay attack.

CWE(s)
CWE-294

Related Threats

MITRE ATT&CK Enterprise Techniques

T1040 Network Sniffing Credential Access
Adversaries may passively sniff network traffic to capture information about an environment, including authentication material passed over the network.
attack.mitre.org →
T1550.003 Pass the Ticket Lateral Movement
Adversaries may “pass the ticket” using stolen Kerberos tickets to move laterally within an environment, bypassing normal system access controls.
attack.mitre.org →
T1550.004 Web Session Cookie Lateral Movement
Adversaries can use stolen session cookies to authenticate to web applications and services.
attack.mitre.org →
T1557 Adversary-in-the-Middle Credential Access
Adversaries may attempt to position themselves between two or more networked devices using an adversary-in-the-middle (AiTM) technique to support follow-on behaviors such as [Network Sniffing](https://attack.
attack.mitre.org →
T1021 Remote Services Lateral Movement
Adversaries may use [Valid Accounts](https://attack.
attack.mitre.org →
T1021.002 SMB/Windows Admin Shares Lateral Movement
Adversaries may use [Valid Accounts](https://attack.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-30079Same product: Openairinterface Oai-Cn5G-Amf
CVE-2025-66786Same product: Openairinterface Oai-Cn5G-Amf
CVE-2026-30075Same product: Openairinterface Oai-Cn5G-Amf
CVE-2026-30078Same product: Openairinterface Oai-Cn5G-Amf
CVE-2025-65805Same product: Openairinterface Oai-Cn5G-Amf
CVE-2023-34553Shared CWE-294
CVE-2024-38284Shared CWE-294
CVE-2023-45794Shared CWE-294
CVE-2023-20123Shared CWE-294
CVE-2024-49595Shared CWE-294

Affected Assets

openairinterface
oai-cn5g-amf
2.2.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V10.4.16
  • V10.5.1

Mitigating Controls (NIST 800-53 r5) AI

SC-23 Session Authenticity good match

Session authenticity mechanisms directly stop replay of captured authentication traffic by enforcing freshness or cryptographic binding.

SC-8 Transmission Confidentiality and Integrity good match

Transmission integrity (with anti-replay) stops captured messages from being accepted as valid later.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-04 mostly match
prevents

Protecting and verifying identity assertions prevents replay of captured authentication material.

PR.DS-02 mostly match
prevents

Encryption and integrity protections for data-in-transit directly block capture-replay of credentials or tokens.

DE.CM-01 partial match
prevents

Network monitoring may detect anomalous replays after the fact but does not prevent the design flaw.

PR.AA-03 partial match
prevents

Strong authentication methods can reduce replay risk but do not inherently address captured messages.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.24 Use of cryptography mostly match
prevents

Cryptographic protections (e.g., nonces, timestamps, message authentication codes) make captured authentication messages unusable for replay.

A.8.5 Secure authentication mostly match
prevents

Secure authentication mechanisms directly prevent replay attacks by requiring fresh, non-replayable credentials or tokens.

A.8.20 Networks security partial match
mitigates

Network security controls such as encryption and integrity protection reduce the feasibility of capturing and replaying authentication traffic.

A.8.26 Application security requirements partial match
prevents

Application security requirements can mandate replay-resistant authentication designs, but the control itself does not prescribe the technical measures.

References