CVE-2026-40247 Details
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 reading 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 data is returned alongside the 404 response. An unauthenticated attacker with access to the 5G Service Based Interface can read arbitrary Traffic Influence Subscriptions, including SUPIs/IMSIs, DNNs, S-NSSAIs, and callback URIs, by supplying any value for the influenceId path segment. A patched version was not available at the time of publication.
A vulnerability exists in the free5GC UDR service in versions through 4.2.1, where improper path validation allows unauthenticated access to Traffic Influence Subscriptions. The issue arises because the handler for reading subscriptions does not correctly validate the influenceId path segment. Instead of rejecting invalid values, the handler continues execution after sending a 404 response, inadvertently disclosing subscription data. This vulnerability can be exploited by sending a request with any influenceId value, while a valid subscriptionId is required to retrieve the subscription data. The exposed information may include sensitive details such as SUPIs/IMSIs, DNNs, S-NSSAIs, and callback URIs.
Users can update to the patched version of free5GC where this vulnerability has been addressed by adding the missing return statement in the UDR service's API data repository handling function.
Metrics
CVSS 4.0 Severity and Vector Strings:
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Apr 17, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/free5gc/free5gc/security/advisories/GHSA-x5r2-r74c-3w28 | [email protected] | ExploitMitigationThird Party Advisory |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-285 | Improper Authorization | [email protected] |
| CWE-636 | Not Failing Securely ('Failing Open') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| free5gc free5gc | <= 4.2.1 |
CPE
Remediation
| |
Change History
4 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Apr 21, 2026 | Initial Analysis | [email protected] |
| Apr 16, 2026 | New CVE Received | [email protected] |