CVE-2026-44321

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 inbound OAuth2 middleware. The POST /upi/v1/upNodesLinks create-or-update handler accepts attacker-controlled JSON and passes it directly into UpNodesFromConfiguration(), which calls logger.InitLog.Fatalf(...) on several validation failures. One confirmed path is the UE-IP-pool overlap check: a single unauthenticated POST that adds a new UPF whose pool overlaps an existing UPF terminates the entire SMF process (docker ps shows Exited (1)), not just the goroutine. This vulnerability is fixed in 4.2.2.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/free5gc/free5gc/issues/906	Exploit Issue Tracking
https://github.com/free5gc/free5gc/security/advisories/GHSA-44qj-cghf-9p97	Exploit Vendor Advisory
https://github.com/free5gc/smf/commit/e0974e07ddab44a67d36a563cca383b2449e33e5	Patch
https://github.com/free5gc/smf/pull/203	Issue Tracking Patch
https://github.com/free5gc/free5gc/security/advisories/GHSA-44qj-cghf-9p97	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-27 17:16

Updated : 2026-06-17 10:50

NVD link : CVE-2026-44321

Mitre link : CVE-2026-44321

CVE.ORG link : CVE-2026-44321

JSON object : View

Products Affected

free5gc

free5gc

CWE

CWE-306

Missing Authentication for Critical Function

CWE-617

Reachable Assertion

CWE-862

Missing Authorization

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