CVE-2026-44316
HighSummary
In versions prior to 4.2.2, the PCF POST /npcf-smpolicycontrol/v1/sm-policies handler in free5GC panics due to a nil-pointer dereference when an OpenAPI consumer call returns a 404 error. Instead of returning an error, it continues execution, leading to a panic and returning an HTTP 500 error.
Risk Assessment
An attacker can exploit this vulnerability to trigger a 500 error, potentially leading to unpredictable system behavior and service availability loss. Additionally, the lack of authorization for this endpoint in version 4.2.1 increases the risk of unauthorized access.
Recommendation
It is recommended to upgrade to version 4.2.2 or later to fix this vulnerability. Proper authorization mechanisms should also be implemented for the PCF Npcf_SMPolicyControl endpoint.
Original NVD description (English source)
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's PCF POST /npcf-smpolicycontrol/v1/sm-policies handler (HandleCreateSmPolicyRequest) panics with a nil-pointer dereference when a downstream OpenAPI consumer call (UDR lookup) returns 404 Not Found and the consumer wrapper returns err != nil together with a nil response struct. The handler logs the OpenAPI error and continues executing instead of returning, then dereferences the nil response struct on a subsequent line and panics. Gin recovery converts the panic into HTTP 500, so a single attacker-shaped POST returns 500 instead of a clean 4xx whenever the downstream lookup fails. The PCF process keeps running. The trigger is a single POST containing input that causes the downstream UDR lookup to fail (e.g. an unknown DNN). In 4.2.1 this endpoint is also reachable WITHOUT an Authorization header because the PCF Npcf_SMPolicyControl route group is mounted without inbound auth middleware. This vulne