VYPR
High severityNVD Advisory· Published Mar 20, 2026· Updated Mar 20, 2026

free5GC UDM incorrectly returns 500 for empty supi path parameter in PATCH sdm-subscriptions reques

CVE-2026-33192

Description

Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. In versions prior to 1.4.2, the UDM incorrectly converts a downstream 400 Bad Request (from UDR) into a 500 Internal Server Error when handling PATCH requests with an empty supi path parameter. Additionally, the UDM incorrectly translates the PATCH method to PUT when forwarding to UDR, indicating a deeper architectural issue. This leaks internal error handling behavior, making it difficult for clients to distinguish between client-side errors and server-side failures. The issue has been patched in version 1.4.2.

Affected packages

Versions sourced from the GitHub Security Advisory.

PackageAffected versionsPatched versions
github.com/free5gc/udmGo
< 1.4.21.4.2

Affected products

1

Patches

0

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

5

News mentions

0

No linked articles in our index yet.