CVE-2026-44328

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. On top of that, the DELETE /upi/v1/upNodesLinks/{upNodeRef} handler unconditionally dereferences upNode.UPF after the type-guarded async release, even though AN-typed nodes are constructed without a UPF object. As a result, a single unauthenticated DELETE /upi/v1/upNodesLinks/gNB1 request crashes the handler with a nil-pointer panic AND mutates the in-memory user-plane topology before panicking (the UpNodeDelete(upNodeRef) line runs first). This is an unauthenticated, state-mutating panic-DoS sink that an off-path network attacker can trigger by name against any AN entry. This vulnerability is fixed in 4.2.2.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/free5gc/free5gc/issues/905	Exploit Issue Tracking
https://github.com/free5gc/free5gc/security/advisories/GHSA-p9mg-74mg-cwwr	Exploit Vendor Advisory
https://github.com/free5gc/smf/commit/b57bc48081c3d3a2f333d02eb78e4fd31a120deb	Patch
https://github.com/free5gc/smf/pull/199	Issue Tracking Patch
https://github.com/free5gc/free5gc/issues/905	Exploit Issue Tracking
https://github.com/free5gc/free5gc/security/advisories/GHSA-p9mg-74mg-cwwr	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-2026-44328

Mitre link : CVE-2026-44328

CVE.ORG link : CVE-2026-44328

JSON object : View

Products Affected

free5gc

free5gc

CWE

CWE-306

Missing Authentication for Critical Function

CWE-476

NULL Pointer Dereference

CWE-862

Missing Authorization

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