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MEDIUM

free5GC: UDR Improper ueId validation in free5GC EE subscription handlers allows arbitrary identifier persistence

Published Sep 15, 2026

Description

free5GC is an open-source implementation of the 5G core network. In 4.2.3 and earlier, HandleCreateEeSubscriptions and HandleQueryeesubscriptions in free5gc/udr internal/sbi/api_datarepository.go validate the ueId path value with a regular expression whose final .+ alternative accepts every non-empty string instead of restricting identifiers to supported SUPI and GPSI formats. An actor with network reachability to the UDR SBI can submit a non-3GPP identifier to /nudr-dr/v2/subscription-data/{ueId}/context-data/ee-subscriptions, causing the identifier to pass validation and enter the normal create or query flow. The advisory does not independently establish whether authentication is required. Invalid identifiers can be persisted and retrieved as subscription records, enabling unauthorized data creation, UDR namespace pollution, persistent subscriber-metadata corruption, and interference with downstream components that trust stored identifiers to use valid 3GPP formats. The exposure is most relevant in lab, test, or loosely segmented service-based-interface deployments where direct UDR access is possible.

Affected products

Remediation

No remediation recorded yet.

References (3)

Change history (0)

No recorded changes yet.

Sources
CVE.org / MITRE
Status PUBLISHED
Assigner GitHub_M
Published Sep 15, 2026
Updated Sep 15, 2026
Reserved May 19, 2026
CISA Vulnrichment
Updated Sep 15, 2026
NVD
Status Received
Modified Sep 15, 2026
Red Hat
Severity n/a
Public date n/a
ENISA EUVD
Assigner GitHub_M
Published Sep 15, 2026
Updated Sep 15, 2026
Exploited since n/a
EUVD-2026-78766 GHSA-6GXQ-GPR8-XGJP