CVE-2026-44329
CriticalSummary
In versions prior to 4.2.2, free5GC's SMF does not implement OAuth2/bearer-token authorization for the UPI management route group, allowing attackers to access UPI endpoints without an authorization header.
Risk Assessment
Attackers can perform read, write, and delete operations on UPI endpoints, potentially leading to unauthorized access and manipulation of data.
Recommendation
It is recommended to upgrade to version 4.2.2 or later to mitigate this vulnerability.
Original NVD description (English source)
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 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.