TI-2026-25617 Aliases CVE-2026-33192 GHSA-5rvc-5cwx-g5x8

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

HIGH 77CWE-209Published 2026-03-20 · Updated 2026-03-20

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: Information disclosure
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-209.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00333 26th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix Fixed free5gc (free5gc): 1.4.2github.com/free5gc/udm (Go): 1.4.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
free5gc	free5gc	before 1.4.2	1.4.2	Patch available	CNA
—	github.com/free5gc/udm (Go)	before 1.4.2	1.4.2	Patch available	GHSA-5rvc-5cwx-g5x8

free5gc Vendorfree5gc Affected before 1.4.2 Fixed in 1.4.2 Patch available CNA
github.com/free5gc/udm (Go) Vendor— Affected before 1.4.2 Fixed in 1.4.2 Patch available GHSA-5rvc-5cwx-g5x8

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:free5gc:udm::::::go::*	before 1.4.2	Vulnerable	free5gc

cpe:2.3:a:free5gc:udm:*:*:*:*:*:go:*:* Versions before 1.4.2 Vulnerable ·free5gc

Remediation

Fix · CNA free5gc (free5gc) Fixed in 1.4.2
Fix · GHSA-5rvc-5cwx-g5x8 github.com/free5gc/udm (Go) Fixed in 1.4.2 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2026-33192
2026-10-03 Alias added: GHSA-5rvc-5cwx-g5x8

References

Exploit 1

https://github.com/free5gc/free5gc/issues/784

Patch 2

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2026-33192

Other 1

https://github.com/free5gc/udm

TI-2026-25506 free5GC UDM DataChangeNotification Procedure Panic Due to Nil Pointer Dereference CVSS 4.0HIGH 8.7
TI-2026-25507 free5GC UDM incorrectly returns 500 for empty supi path parameter in DELETE sdm-subscriptions request CVSS 4.0MEDIUM 6.9
TI-2026-25616 free5GC UDM vulnerable to null byte injection in URL path parameters causing 500 Internal Server Error CVSS 4.0HIGH 8.7
TI-2026-22024 free5GC has Improper Input Validation in UDM UEAU Service CVSS 4.0MEDIUM 6.6
TI-2025-42704 free5GC has Null Pointer Dereference in UDM, Leading to Service Panic CVSS 4.0MEDIUM 6.6
TI-2025-42703 free5GC has Improper Input Validation in UDM, Leading to Information Exposure CVSS 4.0MEDIUM 6.6

See all 8 →

Sources

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