CVE-2026-47780 free5GC: UDR Improper ueId validation in free5GC EE subscription handlers allows arbitrary identifier persistence
Attackers can inject invalid subscriber identifiers into the UDR, causing data corruption and namespace pollution in 5G core deployments.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-47780?
CVE-2026-47780 is a medium-severity vulnerability in free5gc, published on 15 Sep 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 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.
Weakness: CWE-20
Which versions are affected by CVE-2026-47780?
3 open source packages ship an affected version, including github.com/free5gc/udr.
| Package | Affected | Fixed in |
|---|---|---|
github.com/free5gc/udr Go | All versions | None |
github.com/free5gc/udr Go | All versions to 1.4.3 | None |
github.com/free5gc/udr Go | All versions to 1.4.3 | None |
How do I fix CVE-2026-47780?
Upgrade to a fixed version.
Is CVE-2026-47780 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47780 exists.
Sources
Also known as GHSA-6gxq-gpr8-xgjp, GO-2026-5178.