CWE-478
Missing Default Case in Multiple Condition Expression
The code does not have a default case in an expression with multiple conditions, such as a switch statement.
CVE-2026-33064 (GCVE-0-2026-33064)
Vulnerability from cvelistv5 – Published: 2026-03-20 08:00 – Updated: 2026-03-20 15:42
VLAI?
Title
free5GC UDM DataChangeNotification Procedure Panic Due to Nil Pointer Dereference
Summary
Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions prior to 1.4.2 are vulnerable to procedure panic caused by Nil Pointer Dereference in the /sdm-subscriptions endpoint. A remote attacker can cause the UDM service to panic and crash by sending a crafted POST request to the /sdm-subscriptions endpoint with a malformed URL path containing path traversal sequences (../) and a large JSON payload. The DataChangeNotificationProcedure function in notifier.go attempts to access a nil pointer without proper validation, causing a complete service crash with "runtime error: invalid memory address or nil pointer dereference". Exploitation would result in UDM functionality disruption until recovery by restart. This issue has been fixed in version 1.4.2.
Severity ?
CWE
- CWE-478 - Missing Default Case in Multiple Condition Expression
Assigner
References
| URL | Tags | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||
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Mitigation
Phase: Implementation
Description:
- Ensure that there are no cases unaccounted for when adjusting program flow or values based on the value of a given variable. In the case of switch style statements, the very simple act of creating a default case can, if done correctly, mitigate this situation. Often however, the default case is used simply to represent an assumed option, as opposed to working as a check for invalid input. This is poor practice and in some cases is as bad as omitting a default case entirely.
No CAPEC attack patterns related to this CWE.