CVE-2026-14623: OMEC AMF NGAP DoS Vulnerability – Patch Guidance

Technical summary

CVE-2026-14623 is a denial-of-service vulnerability in the OMEC Project AMF's NGAP Message Handler component. The RRCInactiveTransitionReport function fails to properly validate or sanitize incoming NGAP messages, allowing an authenticated remote attacker to trigger resource exhaustion or improper state transitions. The vulnerability is classified under CWE-404 (Improper Resource Validation) and carries a CVSS 3.1 score of 4.3 (Medium severity). The attack vector is network-based with low complexity; authentication is required to execute the exploit. The impact is limited to availability (denial of service) with no confidentiality or integrity compromise.

Business impact

Telecommunications operators and enterprises deploying OMEC AMF infrastructure face potential service disruptions affecting mobile user authentication and session management. While the severity is rated Medium, the real-world impact depends on network architecture: if the AMF is a single point of failure without redundancy, even intermittent DoS attacks could degrade user experience and call completion rates. Organizations with proper load balancing and failover mechanisms will experience reduced risk. The public disclosure of exploit code increases the window of risk before patching is completed.

Affected systems

OMEC Project AMF versions up to and including 2.1.1 are affected. OMEC (Open Mobile Evolved Core) is an open-source 5G core network implementation; this vulnerability impacts deployments in private 5G networks, operator labs, and test environments, as well as any production systems built on these components. Verify your specific OMEC deployment version against the vendor advisory to confirm exposure.

Exploitability

This vulnerability requires network-level access and valid authentication credentials—an attacker must have legitimate user or service account access to the network where the AMF operates. The attack itself is straightforward: sending a specially-crafted NGAP message to the RRCInactiveTransitionReport handler does not require user interaction or system-level privileges. The publicly disclosed exploit code lowers the barrier to weaponization, though the authentication requirement prevents opportunistic, large-scale external attacks. Insider threats or compromised service accounts pose the most credible immediate risk.

Remediation

Apply the patch identified as commit 34bc6724acc97dba1f8691e586da95b042cb612d to upgrade your OMEC AMF deployment. Review the patch changelog to confirm it addresses the RRCInactiveTransitionReport validation issue. For organizations unable to patch immediately, implement network segmentation and access controls to restrict NGAP message sources to trusted elements; monitor AMF logs for repeated NGAP message patterns that may indicate exploitation attempts.

Patch guidance

Retrieve the patch commit 34bc6724acc97dba1f8691e586da95b042cb612d from the OMEC Project repository and test it in a non-production environment before deployment. Verify the patch version meets your operational requirements and does not introduce compatibility issues with dependent components (e.g., RAN elements, UPF). Plan a maintenance window for patching; coordinate with network teams to ensure graceful failover if your deployment has redundancy. Post-patch, validate that NGAP message handling resumes normal behavior under load.

Detection guidance

Monitor NGAP message processing logs for anomalous RRCInactiveTransitionReport messages, including those with malformed payloads or unexpected state transitions. Set alerts on AMF resource utilization spikes (CPU, memory) that correlate with NGAP message ingestion. Network-based detection can focus on NGAP traffic patterns from authenticated users; unusual burst rates or repetitive message sequences from a single source warrant investigation. Enable detailed NGAP protocol logging if your platform supports it.

Why prioritize this

While the CVSS score is Medium (4.3), prioritize this for near-term remediation due to the publicly disclosed exploit and low attack complexity. Authentication requirement limits the threat actor pool but does not eliminate insider risk. The impact on availability in a production 5G network, especially if AMF redundancy is absent, could justify accelerated patching. Organizations in the OMEC ecosystem should treat this as higher priority than the base CVSS suggests.

Risk score, explained

The CVSS 3.1 score of 4.3 reflects a network-accessible, low-complexity attack that requires user-level authentication and causes only availability impact. This places it in the Medium severity band. However, the score does not fully capture deployment-specific factors: a single-point-of-failure AMF in production carries higher business risk than an AMF in a lab environment. The public exploit disclosure increases practical exploitability; threat actors can repurpose published code without significant reverse engineering effort.

Frequently asked questions