CVE-2026-33192 - free5GC UDM incorrectly returns 500 for empty supi path parameter in PATCH sdm-subscriptions reques

Back Back to CVE browser

HIGH

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

Published Mar 20, 2026

8.7

HIGH

CVSS 4.0

EPSS 0.40%

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 products

Vendor Free5gc Product Free5gc Default
n/a
- Version
  < 1.4.2
  Status
  affected
  Constraints
  -

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor

Product

Default status

Versions

Free5gc

n/a

Version	Status	Constraints
< 1.4.2	affected	-

Ecosystem	Package	Introduced	Fixed
Go	github.com/free5gc/udm	0	1.4.2

Remediation

No remediation recorded yet.

Weaknesses (1)

CWE-209

References (6)

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-13634
Advisory
https://github.com/advisories/GHSA-5rvc-5cwx-g5x8
Advisory
https://github.com/free5gc/free5gc/issues/784
x_refsource_MISCExploitIssue TrackingPatchVendor Advisory
https://github.com/free5gc/free5gc/security/advisories/GHSA-5rvc-5cwx-g5x8
x_refsource_CONFIRMPatchVendor Advisory
https://github.com/free5gc/udm/pull/79
x_refsource_MISCIssue TrackingPatch
https://nvd.nist.gov/vuln/detail/CVE-2026-33192

Link	Providers	Tags
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-13634		Advisory
https://github.com/advisories/GHSA-5rvc-5cwx-g5x8		Advisory
https://github.com/free5gc/free5gc/issues/784		x_refsource_MISCExploitIssue TrackingPatchVendor Advisory
https://github.com/free5gc/free5gc/security/advisories/GHSA-5rvc-5cwx-g5x8		x_refsource_CONFIRMPatchVendor Advisory
https://github.com/free5gc/udm/pull/79		x_refsource_MISCIssue TrackingPatch
https://nvd.nist.gov/vuln/detail/CVE-2026-33192