CVE-2026-44319
HighSummary
In versions prior to 4.2.2, free5GC's NEF terminates the entire process when a stored PFD-subscription notifyUri cannot be reached. An attacker can create a PFD subscription with an attacker-chosen notifyUri and trigger a PFD change, leading to NEF failure.
Risk Assessment
This vulnerability can lead to a complete shutdown of NEF, resulting in the loss of availability of the SBI interface until a restart occurs. It may impact the operation of the 5G network and service availability.
Recommendation
It is recommended to upgrade to version 4.2.2 or later to mitigate this vulnerability. Additionally, monitor and secure PFD subscriptions against unauthorized access.
Original NVD description (English source)
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF terminates the entire process when a stored PFD-subscription notifyUri cannot be reached. In PfdChangeNotifier.FlushNotifications(), the notifier calls NnefPFDmanagementNotify(...) and on any delivery error invokes logger.PFDManageLog.Fatal(err), which is os.Exit(1)-equivalent in Go. An attacker who can create a PFD subscription with an attacker-chosen notifyUri and then trigger a PFD change can deterministically kill NEF on the asynchronous delivery attempt -- the process exits with status 1, dropping NEF's entire SBI surface until restart. This vulnerability is fixed in 4.2.2.