CVE-2026-33192 free5GC UDM incorrectly returns 500 for empty supi path parameter in PATCH sdm-subscriptions reques
An attacker can trigger internal error messages in free5GC UDM by sending malformed requests, revealing internal server behavior and error handling details.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-33192?
CVE-2026-33192 is a high-severity vulnerability in free5gc, published on 20 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-209
Which versions are affected by CVE-2026-33192?
3 open source packages ship an affected version, including github.com/free5gc/udm. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/free5gc/udm Go | All versions | 1.4.2 |
github.com/free5gc/udm Go | All versions | 1.4.2 |
github.com/free5gc/udm Go | All versions | 1.4.2 |
Products include Free5gc Udm.
How do I fix CVE-2026-33192?
Upgrade github.com/free5gc/udm to 1.4.2 or later.
Is CVE-2026-33192 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33192 exists.
Other vulnerabilities in free5gc
- CVE-2026-33064 free5GC UDM DataChangeNotification Procedure Panic Due to Nil Pointer Dereference
- CVE-2026-33191 free5GC UDM vulnerable to null byte injection in URL path parameters causing 500 Internal Server Error
- CVE-2023-46324 free5GC udm vulnerable to Invalid Curve Attack
- CVE-2026-33065 free5GC UDM incorrectly returns 500 for empty supi path parameter in DELETE sdm-subscriptions request
- CVE-2026-27642 free5GC has Improper Input Validation in UDM UEAU Service
Sources
Also known as GHSA-5rvc-5cwx-g5x8, GO-2026-4755, ROOT-OS-UBUNTU-2204-CVE-2026-33192.