free5GC UDR is the Policy Control Function (PCF) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. A memory leak vulnerability in versions prior to 1.4.3 allows any unauthenticated attacker with network access to the PCF SBI interface to cause uncontrolled memory growth by sending repeated HTTP requests to the OAM endpoint. The root cause is a `router.Use()` call inside an HTTP handler that registers a new CORS middleware on every incoming request, permanently growing the Gin router's handler chain. This leads to progressive memory exhaustion and eventual Denial of Service of the PCF, preventing all UEs from obtaining AM and SM policies and blocking 5G session establishment. Version 1.4.3 contains a patch.

A vulnerability has been found in Free5GC pcf up to 1.4.1. This affects the function HandleCreateSmPolicyRequest of the file internal/sbi/processor/smpolicy.go. The manipulation leads to null pointer dereference. The attack is possible to be carried out remotely. The exploit has been disclosed to the public and may be used. The identifier of the patch is df535f5524314620715e842baf9723efbeb481a7. Applying a patch is the recommended action to fix this issue.