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
Modified
2026-03-20 15:42
Severity ?
8.7 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
  • CWE-478 - Missing Default Case in Multiple Condition Expression
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.
References
Impacted products
Vendor Product Version
free5gc free5gc Version: < 1.4.2
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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.

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