Cyber Posture

CVE-2026-44329

CriticalPublic PoC

Published: 27 May 2026

Published
27 May 2026
Modified
28 May 2026
KEV Added
Patch
CVSS Score 10.0 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:H
EPSS Score 0.0005 15.0th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-44329 is a critical-severity Missing Authentication for Critical Function (CWE-306) vulnerability in Free5Gc Free5Gc. Its CVSS base score is 10.0 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 15.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190).
Threat & Defense Details

Likely Mitigating ControlsAI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-306 CWE-862

Requiring identification and rationale for actions allowed without authentication ensures critical functions are not left unprotected by forcing review of authentication requirements.

addresses: CWE-306 CWE-862

Authorizing mobile device connections to organizational systems ensures authentication is performed for this critical access function.

addresses: CWE-862 CWE-306

Always invoking the reference monitor prevents missing authorization checks for protected resources.

addresses: CWE-306 CWE-862

Auditing sessions makes it possible to detect access to critical functions without required authentication.

addresses: CWE-306 CWE-862

The assessment process confirms authentication is present and effective for critical functions, preventing exploitation from missing authentication.

addresses: CWE-306 CWE-862

Certification assesses that critical functions have required authentication controls in place.

addresses: CWE-862 CWE-306

Requiring authorization servers ensures authorization is performed for protected functions.

addresses: CWE-306 CWE-862

Tailoring determines which functions require authentication and selects the appropriate baseline or compensating authentication controls.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

Missing auth on network-reachable SMF SBI/UPI endpoints directly enables exploitation of a public-facing 5G core component (T1190).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without OAuth2/bearer-token authorization middleware. A network attacker who can reach SMF on the SBI can hit UPI endpoints with…

more

no Authorization header at all, and the requests reach the SMF business handlers. In the running Docker lab this was directly demonstrated for read (GET /upi/v1/upNodesLinks), write (POST /upi/v1/upNodesLinks with attacker-controlled UP-node and link payload), and delete (DELETE /upi/v1/upNodesLinks/{nodeID}) operations. This vulnerability is fixed in 4.2.2.

Deeper analysisAI

Automated synthesis unavailable for this CVE.

Details

CWE(s)
OWASP Top 10 Web 2025

Affected Products

free5gc
free5gc
≤ 4.2.2

EU & UK References

Regulatory context (EU CRA / NIS2 / DORA / UK NIS Regulations)

EU Cyber Resilience Act — coordinated disclosure

Critical and high-severity vulnerabilities in products with digital elements may trigger coordinated-disclosure obligations under the EU Cyber Resilience Act (CRA, Regulation 2024/2847). Manufacturers placing products on the EU market must notify ENISA and the relevant CSIRTs without undue delay once active exploitation is known.

References