CVE-2025-69251: free5GC has Improper Input Validation in UDM, Leading to Information Exposure

Published Feb 23, 2026
·
Updated

free5gc UDM provides Unified Data Management (UDM) for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, remote attackers can inject control characters (e.g., %00) into the ueId parameter, triggering internal URL parsing errors (net/url: invalid control character). This exposes system implementation details and can aid in service fingerprinting. All deployments of free5GC using the UDM NudmUECM service may be affected. free5gc/udm pull request 76 contains a fix for the issue. No direct workaround is available at the application level. Applying the official patch is recommended.

Affected Software

2 affected components
free5gc/udm<=1.4.1
free5gc Udm Go<=1.4.1

Event History

Feb 23, 2026
CVE Published
via MITRE·11:53 PM
Data Sourced
via MITRE·11:53 PM
DescriptionWeakness
Feb 24, 2026
Data Sourced
via NVD·12:16 AM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2025-69251?

CVE-2025-69251 has a high severity rating due to its potential to lead to information exposure via improper input validation.

2

How do I fix CVE-2025-69251?

To fix CVE-2025-69251, upgrade free5GC UDM to version 1.4.2 or higher, where this vulnerability has been addressed.

3

What systems are affected by CVE-2025-69251?

CVE-2025-69251 affects all versions of free5GC UDM up to and including 1.4.1.

4

What is the impact of CVE-2025-69251 on free5GC UDM?

The impact of CVE-2025-69251 includes the risk of information exposure due to remote attackers being able to inject control characters.

5

Who can exploit CVE-2025-69251?

CVE-2025-69251 can be exploited by remote attackers who can send specially crafted requests to the vulnerable UDM component.

Contact

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