# CVE-2026-30070: free5GC UDM HandleGetSharedData denial of service

Source: https://junglewise.ai/threats/cve-2026-30070-free5gc-udm-handlegetshareddata-denial-of-service  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-27. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-30070 · Severity: high · CVSS 7.5 · Published 2026-08-27

free5GC is an open-source 5G mobile network core software. A flaw in the Subscriber Data Management (SDM) component causes the service to crash when receiving HTTP requests with a missing 'supported-features' query parameter. An attacker can send crafted requests to render the UDM (User Data Management) service unavailable, disrupting mobile subscriber authentication and data services.

Technologies: [free5GC](https://junglewise.ai/threats/technologies/free5gc). Vendors: [free5GC](https://junglewise.ai/threats/vendors/free5gc).

## Quick answers

**Is CVE-2026-30070 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-30070 being exploited in the wild.

**How severe is CVE-2026-30070?** High severity, with a CVSS score of 7.5, published 27 August 2026.

**Which products and versions are affected?** free5GC v4.0.1.

**Is there a fix for CVE-2026-30070?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-30070 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-30070?** Check whether you run free5GC at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is an out-of-bounds array access in the HandleGetSharedData function of free5GC's UDM SDM module. The function assumes the 'supported-features' query parameter is present and attempts to access its first element (supportedFeatures[0]) without validating slice length or presence. When the parameter is omitted or empty, a Go runtime panic ("index out of range") is triggered, crashing the service and causing a denial of service. Attack vector is network-based; no authentication is required. A simple HTTP GET request to /nudm-sdm/v2/shared-data without the query parameter is sufficient to trigger the crash. Patches are expected to add proper validation of the supportedFeatures slice before access.

## Affected products

- free5GC free5GC v4.0.1

## Timeline

- 2026-01-01: disclosed: Bug reported on GitHub issue #762
- 2026-08-27: advisory: CVE-2026-30070 published

## References

- [https://github.com/free5gc/free5gc/issues/762](https://github.com/free5gc/free5gc/issues/762)

## Related threats

- [Free5GC SMF resource exhaustion in PFCP session establishment](https://junglewise.ai/threats/cve-2026-106805-a-resource-exhaustion-issue-exists-in-free5gc-v4-2-3-during-pfcp)
- [Free5GC race condition in GMM handler RanUe context access](https://junglewise.ai/threats/cve-2026-94043-a-vulnerability-was-determined-in-free5gc-up-to-4-2-3-this)
- [Free5GC UPF nil pointer dereference in PFCP Session Report](https://junglewise.ai/threats/cve-2026-75439-free5gc-upf-nil-pointer-dereference-in-pfcp-session-report)
- [free5GC NRF input validation bypass in NF profile registration](https://junglewise.ai/threats/cve-2026-55068-free5gc-nrf-input-validation-bypass-in-nf-profile-registration)
- [free5gc NSSF nil pointer dereference in NssaiAvailabilitySubscriptionCreate](https://junglewise.ai/threats/cve-2026-30073-free5gc-nssf-nil-pointer-dereference-in)