Vulnerability · Published Sep 15, 2026 · Assigned by GitHub_M

CVE-2026-47780free5GC: UDR Improper ueId validation in free5GC EE subscription handlers allows arbitrary identifier persistence

Medium 6.9

In plain English

A medium-severity improper input validation in free5gc from free5gc. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities).

Severity (CVSS 4.0)6.9Medium
Exploit odds (30 days)0.5%top 54.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official 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 packages & fixed versions

EcosystemPackageFixed inAdvisory
Gogithub.com/free5gc/udrno fix listedGHSA-6gxq-gpr8-xgjp
Gogithub.com/free5gc/udrno fix listedGO-2026-5178

Affected products (as reported)

VendorProductVersions
free5gc free5gc <= 4.2.2

Weakness: CWE-20 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

References