Vulnerability Description
free5GC is an open-source implementation of the 5G core network. In versions 4.2.1 and below of the UDR service, the handler for creating or updating Traffic Influence Subscriptions checks whether the influenceId path segment equals subs-to-notify, but does not return after sending the HTTP 404 response when validation fails. Execution continues and the subscription is created or overwritten regardless. An unauthenticated attacker with access to the 5G Service Based Interface can create or overwrite arbitrary Traffic Influence Subscriptions, including injecting attacker-controlled notificationUri values and arbitrary SUPIs, by supplying any value for the influenceId path segment. A patched version was not available at the time of publication.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Free5Gc | Free5Gc | <= 4.2.1 |
Related Weaknesses (CWE)
References
- https://github.com/free5gc/free5gc/security/advisories/GHSA-jgq2-qv8v-5cmjExploitVendor Advisory
- https://github.com/free5gc/free5gc/security/advisories/GHSA-jgq2-qv8v-5cmjExploitVendor Advisory
FAQ
What is CVE-2026-40248?
CVE-2026-40248 is a vulnerability with a CVSS score of 7.5 (HIGH). free5GC is an open-source implementation of the 5G core network. In versions 4.2.1 and below of the UDR service, the handler for creating or updating Traffic Influence Subscriptions checks whether the...
How severe is CVE-2026-40248?
CVE-2026-40248 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-40248?
Check the references section above for vendor advisories and patch information. Affected products include: Free5Gc Free5Gc.