# 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.

- **Severity:** Medium 6.9 (`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`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Sep 2026
- **Updated:** 15 Sep 2026
- **Also known as:** GHSA-6gxq-gpr8-xgjp, GO-2026-5178

## 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 (Improper Input Validation)

## Which versions are affected by CVE-2026-47780?

3 open source packages ship an affected version, including github.com/free5gc/udr.


| Package | Ecosystem | 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.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-47780 and fix it if it is affected.

What it is: 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.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47780 exists.

Affected packages and fixed versions:
- github.com/free5gc/udr (Go): affected all versions; no fix listed
- github.com/free5gc/udr (Go): affected all versions up to 1.4.3; no fix listed
- github.com/free5gc/udr (Go): affected all versions up to 1.4.3; no fix listed

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-47780/ (Markdown: https://insights.sbomify.com/CVE-2026-47780/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-47780
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-47780
- OSV: https://osv.dev/vulnerability/CVE-2026-47780

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-47780/
Summaries are generated and may contain mistakes; the official description above is the record.